Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / P1281 — Accelerator Pedal Position (APP) Sensor 2 Performance

P1281 — Accelerator Pedal Position (APP) Sensor 2 Performance

Detailed page for trouble code P1281.

34,405codes
59brands
11,914generic
22,491specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

P1281

BUICK P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: BUICK
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

CADILLAC P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: CADILLAC
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
206

Browse 206 CADILLAC manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

CADILLAC

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

P1281

CHEVROLET P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: CHEVROLET
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
456

Browse 456 CHEVROLET manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

CHEVROLET

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

P1281

CHRYSLER P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: CHRYSLER
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
193

Browse 193 CHRYSLER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

CHRYSLER

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

P1281

DODGE P — Powertrain

Engine Operating Temp Below Acceptable Range

Brand: DODGE
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

FORD P — Powertrain

Injection Control Pressure Out Of Range High

Brand: FORD
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

GM P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: GM
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

GMC P — Powertrain

Accelerator Pedal Position (APP) Sensor 2 Performance

Brand: GMC
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

HUMMER P — Powertrain

Accelerator Pedal Position Sensor 2 Circuit Performance

Brand: HUMMER
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Repair manuals

Manual library for HUMMER

138

Browse 138 HUMMER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

HUMMER

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

P1281

JEEP P — Powertrain

Engine Operating Temp Below Acceptable Range

Brand: JEEP
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

LINCOLN P — Powertrain

Injection Control Pressure Out Of Range High

Brand: LINCOLN
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
166

Browse 166 LINCOLN manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LINCOLN

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

P1281

MERCURY P — Powertrain

Injection Control Pressure Out Of Range High

Brand: MERCURY
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
296

Browse 296 MERCURY manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

MERCURY

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

P1281

OLDSMOBILE P — Powertrain

Accelerator Pedal Position APP Sensor 2 Performance

Brand: OLDSMOBILE
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

Other P — Powertrain

Injection Control Pressure Out Of Range High

Brand: Other
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
9,191

The library contains 9,191 repair and diagnostic manuals. Choose a brand to open the full manual tree by year, model and trim.

ALFA ROMEO
89
AUDI
1,243
BMW
479
CADILLAC
206
CHEVROLET
456
CHRYSLER
193
DAEWOO
75
FIAT
26
GENESIS
207
HUMMER
138
HYUNDAI
371
ISUZU
86
LAND ROVER
320
LEXUS
280
LINCOLN
166
MERCEDES-BENZ
856
MERCURY
296
MITSUBISHI
406
PORSCHE
136
TESLA
58
TOYOTA
2,126
TRIUMPH
131
VOLKSWAGEN
626
VOLVO
221
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

PLYMOUTH P — Powertrain

Engine Operating Temp Below Acceptable Range

Brand: PLYMOUTH
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

PONTIAC P — Powertrain

Engine Operating Temp Below Acceptable Range

Brand: PONTIAC
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

RAM P — Powertrain

Engine is cold too long

Brand: RAM
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P1281

SATURN P — Powertrain

Accelerator Pedal Position APP Sensor 2 Performance

Brand: SATURN
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or corroded wiring or connector to APP sensor 2
  • Open or short to power or ground in APP sensor 2 circuit
  • Faulty APP sensor (internal failure of sensor 2)
  • Poor or missing reference voltage (5V) or ground at pedal sensor connector
  • Mechanical binding or contamination in pedal assembly affecting sensor output
  • Intermittent connection (broken wire, loose terminal)

Symptoms

  • Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
  • Reduced engine power or limp-home mode (throttle response limited)
  • Delayed or inconsistent throttle response when pressing pedal
  • Possible hesitation or surging during throttle application
  • Vehicle may not accelerate as expected or may go to fail-safe throttle control

What to check

  • Retrieve freeze-frame data and all stored DTCs with a scan tool
  • Visually inspect pedal assembly, connector, and wiring for damage, corrosion, pin push-out, or water intrusion
  • Backprobe the APP connector and observe live data for sensor 1 and sensor 2 while operating the pedal
  • Check for proper reference voltage (nominal 5 V) and good ground at pedal connector
  • Wiggle test: move harness and connector while monitoring sensor data for intermittent changes
  • Compare sensor 1 vs sensor 2 voltages/percentages for linear correlation across pedal travel

Signal parameters

  • Reference voltage (VREF): nominal ~5.0 V (typically 4.75–5.25 V) at pedal connector
  • Sensor 1 & Sensor 2 output (typical analog): at rest ~0.5–1.0 V, at wide-open pedal ~4.0–4.5 V (manufacturer values may vary)
  • Sensor outputs should track linearly and correlate — difference between sensors normally
  • No sudden jumps, dropouts, or intermittent open circuits; no short to battery or ground

Diagnostic algorithm

  1. Connect a scan tool and record DTC P1281 and any related codes; note freeze-frame data
  2. Clear codes, then attempt to re-create condition while monitoring live APP sensor 1 and 2 data
  3. Visually inspect pedal connector and harness for damage, corrosion, bent pins, or water; repair as needed
  4. Backprobe connector: verify VREF ≈5 V and good ground with engine/key ON (do not crank with unsafe tests)
  5. With key ON (engine off), measure APP sensor 1 & 2 voltages at rest and while slowly pressing pedal; confirm smooth, proportional change and correlation between sensors
  6. If voltages are missing or incorrect, trace wiring for opens/shorts to power or ground; perform continuity checks to PCM and inspect splice points
  7. Perform wiggle test on harness while monitoring live data to find intermittent faults
  8. If wiring and connectors test good but sensor 2 is out of spec or does not track sensor 1, replace the accelerator pedal assembly (or sensor if removable) per service procedures
  9. After repair, clear codes and verify proper operation and that code does not return; perform road test to confirm throttle response and no limp mode
  10. If problem persists and all wiring and sensors check good, consider PCM reprogramming or replacement as a last resort (verify TSBs and manufacturer procedures)

Likely causes

  • Wiring harness damage or connector corrosion to APP sensor 2
  • Internal failure of APP sensor 2 in the pedal assembly
  • Poor or lost 5 V reference or ground at the pedal connector
  • Intermittent/open connection revealed by movement (wiring fatigue)
  • Less likely: PCM fault or incorrect software/calibration

Fault status

⚠️ Status
APP Sensor 2 performance fault — PCM detected sensor 2 signal out of expected range or inconsistent with sensor 1. MIL illuminated; throttle control may be limited.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0120 P0121 P0122 P0123 P2135 P2138
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .