General Information

Engine Control

P2138 Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation - General Information

Component Location





General Description

The Electronic Throttle Control (ETC) system is made of the components throttle body, Throttle Position Sensor (TPS) 1 & 2 and Accelerator Position Sensor (APS) 1 & 2. The APS is mounted in the accelerator pedal to detect the opening angle of the accelerator pedal. It has 2 sensors to detect the accelerator position and a malfunction of the accelerator position sensor. The ECM judges the current opening angle of the accelerator pedal from APS 1 & 2, and the ECM controls the throttle motor based on these signals.

DTC Description

ECM sets DTC P2138 if the ECM detects output voltage of the APS 1 is not proportion to APS 2.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data

1. IG key ON.
2. Check sensor data as below.




3. Data Analysis