P2138 - OBD II Trouble Code

Our automotive experts have put together the following information about the P2138 diagnostic trouble code. We've provided the common symptoms that occur when this code is set along with the frequent repairs that address the issues related to the P2138 code.

What Does P2138 Code Mean?

OBD-II Code P2138 is defined as a Throttle/Pedal Position Sensor/Switch "D"/"E" Voltage Correlation

The Throttle Position Sensor/Switch is located on the Throttle Body of the Intake Manifold and the Pedal Position Sensor/Switch is part of the Accelerator Pedal assembly. These sensors tell the engine control module (PCM) how fast the driver wants to go and how quickly it needs to get up to speed. When the PCM detects a problem with this sensor or the circuit for the sensor, it will set this code.The PCM may also limit the speed of the vehicle to 20 miles per hour or less ("Limp home mode") to protect the engine and the driver due to the control module's inability to accurately detect the engine performance being requested.

P2138 Symptoms

• Decreased engine performance
• Engine may enter limp home mode (reduced performance)

Common Problems That Trigger the P2138 Code

• Accelerator Pedal Position (APP) assembly failure
• Powertrain Control Module (PCM) failure
• Throttle Position Sensor (TPS) failure
• Wiring issue