Error Code P2138
Moderate Issue
DTC Code P2138 indicates a correlation issue between Accelerator Pedal Position Sensor 1 and 2, where the Engine Control Module (ECM) detects a discrepancy greater than 10% between the two sensors or both sensors exceed 5% of the learned minimum position.
What symptoms indicate Error Code P2138?
- Engine Light ON: The check engine light or service engine soon warning light illuminates, indicating a potential issue with the accelerator pedal position sensor.
- Reduced Engine Power: The vehicle may experience reduced engine power, affecting acceleration and overall performance.
- Unresponsive Throttle: The throttle may become unresponsive, leading to difficulty in controlling the vehicle's speed.
- Erratic Acceleration: The vehicle may exhibit erratic acceleration behavior, such as sudden surges or hesitations.
What causes OBD code Error Code P2138?
- The accelerator pedal position sensor may be malfunctioning, leading to incorrect readings and triggering the error code.
- An open or shorted harness in the accelerator pedal position sensor can disrupt the signal transmission, causing a correlation error.
- Poor electrical connections in the sensor circuit can result in intermittent or incorrect signals being sent to the ECM.
- A faulty Engine Control Module (ECM) can misinterpret sensor signals, leading to a false error code being generated.
How to fix OBD code Error Code P2138?
- Initial Inspection: Inspect the accelerator pedal assembly for any physical damage or obstructions. Ensure the connectors are securely attached and free from corrosion or damage.
- Check for Related DTCs: Scan the vehicle for any related DTCs, especially those listed in the useful information. Address any additional codes as they may be related to the P2138 issue.
- Test Accelerator Pedal Position Sensors: Using a multimeter, measure the voltage output from both Accelerator Pedal Position Sensor 1 and Sensor 2. Compare the readings to the manufacturer's specifications to ensure they are within range.
- Inspect Wiring and Connectors: Examine the wiring harness and connectors between the accelerator pedal and the Engine Control Module (ECM) for any signs of damage, wear, or corrosion. Repair or replace as necessary.
- Perform ECM Diagnostic: Check the ECM for any software updates or known issues related to the P2138 code. Reprogram or replace the ECM if necessary.
- Conduct a Test Drive: After repairs, conduct a test drive to ensure the issue is resolved and the DTC does not reappear. Monitor the live data for the accelerator pedal position sensors to confirm proper operation.