DTC P2138: Description

WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

This diagnostic compares the accelerator pedal position (APP) sensor 1 input with the APP sensor 2 input. There are 2 APP sensors located at the accelerator pedal that are an integral component of the throttle actuator control (TAC) system. The APP sensors obtain driver input through the accelerator pedal angle. The powertrain control module (PCM) receives the APP sensor input and uses that information to determine the necessary throttle opening. The PCM expects the output of the 2 APP sensors to follow the same linear path. If the 2 sensors report conflicting information to the PCM, this DTC sets. For additional information on the operation of the APP sensor and the TAC system, refer to Throttle Actuator Control (TAC) System Description .