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P2138 GMC Code - Accelerator Pedal Position Sensor 1-2 Correlation

- Code Popularity: 27,761 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 2/3
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What are the Possible Causes of the DTC P2138 GMC?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Accelerator Pedal Position Sensor
  • Accelerator Pedal Position Sensor harness is open or shorted
  • Accelerator Pedal Position Sensor circuit poor electrical connection
  • Faulty Engine Control Module (ECM)
⚠ Does your GMC have Safety Recalls? → Check here

How to Fix the DTC P2138 GMC?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes





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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2138 GMC code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P2138 GMC Description

The Accelerator Pedal Assembly contains 2 Accelerator Pedal Position (APP) sensors. The APP sensors are mounted to the accelerator pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the pedal position. The Engine Control Module (ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.
Both the APP sensors 1 and 2 signal percentages increase as the pedal is depressed, from approximately 0 percent at rest to above 95 percent when fully depressed.
The Diagnostic Trouble Code (DTC) will be set when the ECM detects that APP sensor 1 and APP sensor 2 disagree greater than 10 percent for less than 1 s or the ECM detects that both APP sensor 1 and APP sensor 2 are 5 percent greater than the learned minimum position for less than 1 s.

OBDII Code P2138 GMC - Accelerator Pedal Position Sensor 1-2 Correlation - AutoCodes.com
P2138 GMC Code - Accelerator Pedal Position Sensor 1-2 Correlation

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Code P2138 GMC comments

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