Circuit Description

WARNING: This page is about a different variant/trim than selected.

HINT:

This Electronic Throttle Control System (ETCS) does not use a throttle cable.
This is procedure of accelerator pedal position sensor.

The Accelerator Pedal Position (APP) sensor is mounted in the accelerator pedal to detect the angle of the accelerator pedal. This sensor is electronically controlled and uses Hall-effect elements.

In the accelerator pedal position sensor, the voltage applied to terminals VPA and VPA2 of the ECM changes between 0 V and 5 V in proportion to the angle of the accelerator pedal. The VPA is a signal to indicate the actual accelerator pedal angle and is used for the engine control. VPA2 is used to detect malfunctions of the sensor itself.

The ECM monitors the accelerator pedal angle from VPA and VPA2 signal outputs, and controls the throttle motor based on these signals.

Fig 1: Accelerator Pedal Position Sensor Circuit Diagram And Voltage Curve

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Fig 2: DTC Trouble Detection Chart (DTC P2120, P2122, P2123, P2125, P2127, P2128, P2138)

HINT:

After confirming DTC P2120, P2122, P2123, P2125, P2127, P2128 and P2138, use the hand-held tester or the OBD II scan tool to confirm the accelerator pedal position sensor output voltage.

Fig 3: Accelerator Pedal Position Specific Output Voltage Chart