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Home / DTC / P1228 — Injector Circuit Cylinder 3 Intermittent

P1228 — Injector Circuit Cylinder 3 Intermittent

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Code

P1228

BUICK P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: BUICK
Type: P — Powertrain
Views: UK: 19 EN: 33 RU: 29
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

CADILLAC P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: CADILLAC
Type: P — Powertrain
Views: UK: 19 EN: 34 RU: 29
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

CHEVROLET P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: CHEVROLET
Type: P — Powertrain
Views: UK: 20 EN: 32 RU: 27
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

CHRYSLER P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: CHRYSLER
Type: P — Powertrain
Views: UK: 20 EN: 34 RU: 30
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

FORD P — Powertrain

Wastegate Failed Open Under Pressure

Brand: FORD
Type: P — Powertrain
Views: UK: 22 EN: 36 RU: 28
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

GM P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: GM
Type: P — Powertrain
Views: UK: 20 EN: 33 RU: 36
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

GMC P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: GMC
Type: P — Powertrain
Views: UK: 18 EN: 33 RU: 28
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

HUMMER P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: HUMMER
Type: P — Powertrain
Views: UK: 7 EN: 15 RU: 17
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

JAGUAR P — Powertrain

Mechanical Guard Circuit High Input

Brand: JAGUAR
Type: P — Powertrain
Views: UK: 19 EN: 34 RU: 30
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

KIA P — Powertrain

Fuel Injector 4 Circuit Low Voltage

Brand: KIA
Type: P — Powertrain
Views: UK: 19 EN: 35 RU: 31
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

LAND ROVER P — Powertrain

High input mechanical protection circuit Malfunction in the electronic throttle control circuit Want operation of the fuel pump relay

Brand: LAND ROVER
Type: P — Powertrain
Views: UK: 4 EN: 11 RU: 10
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Workshop Manuals

Repair manuals for LAND ROVER

3

Land Rover Defender 300Tdi — Workshop Manual (1996 model year)

Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
Download

Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)

Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
Short description

Workshop Manual Supplement and Body Repair Manual for the Land Rover Defender. Includes general specifications, maintenance schedules, tuning data and step‑by‑step repair procedures for engine, transmission, suspension, brakes, electrical and body repairs. Covers Defender models from 1999 and 2002 model years.

Contents
Key sections:
  • 01 - INTRODUCTION
  • - Introduction
  • - Dimensions
  • - References
  • - Repairs and replacements
  • - Poisonous substances
  • - Fuel handling precautions
  • - Synthetic rubber
  • - Recommended sealants
  • - Used engine oil precautions
  • - Accessories and conversions
  • - Wheels and tyres
Download

Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)

Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

Land Rover Range Rover Electrical Library (LRL 0453ENG). Comprehensive manual covering fuse details, earth points, system descriptions, diagnostics and connector pin-outs for electrical troubleshooting and repair. Intended for technicians and service workshops.

Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
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Code

P1228

LINCOLN P — Powertrain

Wastegate Failed Open Under Pressure

Brand: LINCOLN
Type: P — Powertrain
Views: UK: 22 EN: 46 RU: 29
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

MERCEDES-BENZ P — Powertrain

yet unknown code on 1997 C 220 CDI

Brand: MERCEDES-BENZ
Type: P — Powertrain
Views: UK: 13 EN: 20 RU: 21
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1228

MERCURY P — Powertrain

Wastegate Failed Open Under Pressure

Brand: MERCURY
Type: P — Powertrain
Views: UK: 21 EN: 35 RU: 29
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

MITSUBISHI P — Powertrain

ETV motor 2

Brand: MITSUBISHI
Type: P — Powertrain
Views: UK: 7 EN: 15 RU: 14
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

OLDSMOBILE P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: OLDSMOBILE
Type: P — Powertrain
Views: UK: 22 EN: 41 RU: 30
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

Other P — Powertrain

Wastegate Failed Open (Under Pressure)

Brand: Other
Type: P — Powertrain
Views: UK: 24 EN: 40 RU: 30
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Workshop Manuals

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Short description

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Contents
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Short description

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Code

P1228

PORSCHE P — Powertrain

Fuel injector, cylinder 4

Brand: PORSCHE
Type: P — Powertrain
Views: UK: 3 EN: 5 RU: 7
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Code

P1228

SAAB P — Powertrain

Injector Cyl. 4, Control Module Output, Short To Ground

Brand: SAAB
Type: P — Powertrain
Views: UK: 4 EN: 4 RU: 9
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Send to email
Code

P1228

SATURN P — Powertrain

Injector Circuit Cylinder 3 Intermittent

Brand: SATURN
Type: P — Powertrain
Views: UK: 18 EN: 33 RU: 30
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
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Send to email
Code

P1228

VOLKSWAGEN P — Powertrain

Cylinder 4 Injector Circuit Short To Ground

Brand: VOLKSWAGEN
Type: P — Powertrain
Views: UK: 20 EN: 34 RU: 35
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Broken or chafed wiring in injector 3 harness
  • Corroded, loose or contaminated connector at injector 3
  • Faulty fuel injector (intermittent internal open/short)
  • Poor or intermittent ground or power supply to injector circuit
  • Intermittent PCM/ECM driver or internal fault
  • Aftermarket alarm/engine immobilizer or recent repair wiring incorrectly routed or spliced

Symptoms

  • Check Engine light illuminated (may be intermittent)
  • Possible rough idle or intermittent misfire on cylinder 3
  • Reduced performance or hesitation under load
  • Poor fuel economy if issue present long enough
  • Intermittent starting issues in some cases

What to check

  • Retrieve freeze frame and diagnostic data with a scan tool; confirm P1228 and any related codes (e.g., misfire P0303).
  • Visually inspect wiring and connector at injector 3 for damage, corrosion, or loose pins.
  • Perform wiggle test on harness while monitoring live data or DTC status to reproduce intermittent behavior.
  • Check injector connector voltage: verify constant 12V (or battery voltage) supply and good ground switching signal with engine cranking/operating.
  • Measure injector coil resistance with ohmmeter (engine off, connector disconnected).
  • Use a noid light or lab scope to confirm injector drive pulses and waveform quality.

Signal parameters

  • Battery supply voltage at injector supply terminal: ~11–14.5 V (key on/engine running).
  • Low-side driver (PCM) output when not energized: open/high (injector supply provides battery voltage).
  • Low-side driver when energized (pulse): near 0 V (ground) during pulse — measured as pulsed voltage at connector. Use oscilloscope for waveform.
  • Typical injector coil resistance (varies by engine): ~2–16 Ω depending on low/high impedance design. Compare to factory spec.
  • Pulse width: typically 1–10 ms depending on RPM/load (varies by engine and operating conditions).

Diagnostic algorithm

  1. Confirm DTC(s) and gather freeze-frame data with a scan tool; note engine conditions when fault set (temp, RPM, load).
  2. Visually inspect injector 3 connector and wiring for physical damage, corrosion, melted insulation or loose pins; repair or clean as required.
  3. With ignition OFF, disconnect injector 3 connector and measure injector resistance. Compare to spec. Replace if out of spec or intermittent when heated/cooled.
  4. With connector connected, backprobe the supply and driver terminals. Verify battery voltage on supply terminal (key ON).
  5. Crank or run engine and check the driver side for pulsed ground using a noid light or oscilloscope. Look for missing pulses or erratic waveform.
  6. Perform wiggle test on harness/connectors while monitoring for code reappearance or waveform interruption. Repair any wiring damage.
  7. Check continuity/resistance between injector connector and PCM pin for opens/shorts. Repair harness as necessary.
  8. Swap injector 3 with another cylinder; if the code follows the injector, replace the injector. If it stays on cylinder 3, focus on wiring/PCM.
  9. Inspect and verify PCM power and ground circuits and related fuses/relays. Replace or reprogram PCM only after wiring and injector verified.
  10. Clear codes and perform road test under the same conditions as freeze-frame to verify repair. Re-scan to confirm no reoccurrence.

Likely causes

  • Damaged or pinched harness near the cylinder head or firewall
  • Corrosion inside the injector electrical connector (water intrusion)
  • Injector coil intermittent failure (opens when hot)
  • Connector terminals pushed out or poor contact
  • Intermittent short to battery or to ground caused by rubbing wire

Fault status

⚠️ Status
P1228 — Injector Circuit Cylinder 3 Intermittent: PCM detected an intermittent/open/short condition in the fuel injector circuit for cylinder 3.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0203 P0200 P0303 P1227 P1229
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

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