DTC P2127: Accelerator Position Sensor 2 Signal Circuit Low Input: General Description

The Accelerator Position Sensor (APS) is part of the Electronic Throttle Control (ETC) system. Along with the Throttle Position Sensor (TPS) signals is sent to the PCM, it controls the needed fuel delivery based on the driver's demand. The APS is divided into APS 1 & 2 and has independent power and ground circuits. APS 2 shows 1/2 the output voltage of APS1. The PCM compares delta (difference) of APS 1 & 2 signals. When a fault exists in either APS 1 or APS 2, the opposite (good) circuit will override and go into limp-home mode.