P2138 – Audi DTC

Audi DTC P2138 – Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle Position Sensor (TPS) failure, Wiring issue

DTC P2138 meaning on Audi

DTC P2138 refers to a problem with the Accelerator Pedal Position (APP) sensor in Audi vehicles. This code indicates that there is a discrepancy between the signals sent by the APP sensor and the Throttle Position Sensor (TPS). The PCM monitors these signals to ensure proper throttle response and engine performance. When the signals do not match, it triggers the DTC P2138, indicating a potential failure in the APP assembly, TPS, or related wiring.

Audi DTC P2138 symptoms

Common symptoms associated with DTC P2138 may include:

• Illuminated check engine light
• Unresponsive or erratic throttle response
• Reduced engine power or limp mode
• Stalling or hesitation during acceleration
• Difficulty maintaining speed

Audi DTC P2138 causes

The causes of DTC P2138 can include:

• Failure of the Accelerator Pedal Position (APP) assembly
• Malfunction of the Powertrain Control Module (PCM)
• Faulty Throttle Position Sensor (TPS)
• Wiring issues such as shorts, opens, or corrosion in the APP or TPS circuits

Audi DTC P2138 seriousness

DTC P2138 is considered a serious issue as it can lead to reduced engine performance and safety concerns. The vehicle may enter limp mode, limiting power and speed, which can be dangerous in certain driving conditions. It is important to address this code promptly to ensure safe operation of the vehicle.

How to diagnose DTC P2138 on Audi

To diagnose DTC P2138, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC P2138.
2. Inspect the wiring and connectors related to the APP and TPS for damage or corrosion.
3. Check the APP sensor and TPS for proper operation using a multimeter.
4. Verify the PCM functionality and check for any software updates or reprogramming needs.
5. Clear the DTC and perform a test drive to see if the code reappears.

How to fix DTC P2138 on Audi step-by-step instructions

To fix DTC P2138, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the APP and TPS.
2. If the APP assembly is faulty, replace it with a new unit.
3. Test the Throttle Position Sensor (TPS) and replace it if necessary.
4. Reprogram or replace the PCM if it is determined to be faulty.
5. Clear the DTC using an OBD-II scanner and perform a test drive to ensure the issue is resolved.

How to erase DTC P2138 on Audi

To erase DTC P2138, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Access the diagnostic menu and select the option to clear or erase DTCs.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and perform a test drive to ensure the code does not return.

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