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Home / DTC / P0404 — EGR A Control Circuit Range/Performance

P0404 — EGR A Control Circuit Range/Performance

Detailed page for trouble code P0404.

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P0404

Generic P — Powertrain

EGR A Control Circuit Range/Performance

Brand: Generic
Type: P — Powertrain
Views: UK: 24 EN: 46 RU: 52
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
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Code

P0404

GWM P — Powertrain

- Incorrect indicator / not adjusted Exhaust gas recirculation sensor

Brand: GWM
Type: P — Powertrain
Views: UK: 7 EN: 14 RU: 12
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P0404

HUMMER P — Powertrain

Exhaust Gas Recirculation (EGR) Open Position Performance

Brand: HUMMER
Type: P — Powertrain
Views: UK: 11 EN: 19 RU: 33
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
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HUMMER · Hummer H3T Base · 2010
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Code

P0404

ISUZU P — Powertrain

Exhaust Gas Recirculation Control Circuit Range/Performance

Brand: ISUZU
Type: P — Powertrain
Views: UK: 14 EN: 31 RU: 31
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
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Code

P0404

LAND ROVER P — Powertrain

Exhaust gas recirculation control - circuit range/ performance

Brand: LAND ROVER
Type: P — Powertrain
Views: UK: 6 EN: 16 RU: 20
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
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Code

P0404

MITSUBISHI P — Powertrain

EGR control valve stuck

Brand: MITSUBISHI
Type: P — Powertrain
Views: UK: 13 EN: 22 RU: 31
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open/short or high resistance in EGR control wiring or connectors
  • Faulty EGR valve, EGR position sensor, or EGR solenoid/actuator
  • Clogged carbon buildup in EGR passages or EGR port restricting movement
  • Failed EGR position sensor or incorrect feedback signal
  • Vacuum supply leak or weak vacuum (vacuum‑operated EGR systems)
  • Faulty PCM or EGR driver circuit

Symptoms

  • Check Engine Light (MIL) illuminated
  • Reduced engine power, hesitation or surging under load
  • Rough idle or stalling, especially when warm
  • Decreased fuel economy
  • Failed emissions test (elevated NOx or other emissions)
  • Intermittent drivability complaints depending on operating conditions

What to check

  • Scan for P0404 and any related or pending codes; record freeze frame and live data
  • Inspect EGR valve/solenoid connectors and wiring for corrosion, breaks, pin damage, or poor fit
  • Backprobe EGR control and feedback pins to verify voltage, ground, and duty signals with a scope or DVOM
  • Check EGR valve movement (vacuum or electric) while commanding EGR open/closed from a scan tool
  • Inspect and clean EGR passages, ports, and intake for carbon blocking
  • Verify vacuum supply and check for leaks on vacuum‑operated EGR systems

Signal parameters

  • Command signal: PWM duty cycle 0–100% when commanded by PCM (varies with load and speed)
  • Control voltage: 0–12 V for many solenoids (check vehicle specifics); feedback sensor typically 0–5 V
  • EGR position sensor feedback: usually 0.5–4.5 V range proportional to position
  • At idle with EGR closed: command low duty/voltage and feedback near closed position; when commanded open, feedback should change noticeably
  • Resistance of typical EGR solenoid: often tens to hundreds of ohms (refer to OEM spec)

Diagnostic algorithm

  1. Retrieve DTCs and freeze frame. Note engine conditions when fault set (temp, load, RPM).
  2. Visually inspect EGR valve/solenoid, harness, and connector for damage, corrosion, or loose pins.
  3. With a scan tool, monitor EGR command (duty/voltage) and EGR feedback/position while commanding EGR on/off. Confirm feedback changes appropriately.
  4. Backprobe the connector and verify power and ground are present at the component with ignition on and engine off as specified.
  5. Measure solenoid/actuator resistance; compare to spec. If out of range, replace the component.
  6. Operate the EGR valve manually (apply vacuum or test voltage) to confirm movement and verify flow to intake. If stuck, remove and clean port/valve or replace if mechanically failed.
  7. Inspect and clean EGR passages and intake ports of carbon deposits that could prevent correct operation.
  8. If wiring is suspected, perform wiggle tests, continuity and voltage drop tests, and repair any damaged wiring or connectors.
  9. If control signal from PCM is absent or incorrect but wiring to component is good, consider PCM driver failure — confirm with scope or known‑good module before replacing.
  10. Clear codes and perform test drive to confirm repair; recheck for recurrence and related codes.

Likely causes

  • Corroded or damaged connector/pin at EGR valve/solenoid
  • Stuck or mechanically seized EGR valve due to carbon deposits
  • Failed EGR solenoid/actuator that does not respond to command
  • Broken or shorted harness between PCM and EGR component
  • Bad EGR position sensor producing out‑of‑range feedback

Fault status

⚠️ Status
PCM detected EGR A control or feedback signal out of expected range/performance. EGR command and/or position is not matching expected values, indicating a control circuit, actuator, sensor, or mechanical restriction issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

P0401 P0402 P0403 P0405 P0406 P0407
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Keep it short and practical. Up to 500 characters.
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