Circuit Description

The accelerator pedal position (APP) sensors 1 and 2 are located within the accelerator pedal assembly. Each sensor has the following circuits:

• A 5-volt reference circuit
• A low reference circuit
• A signal circuit

This provides the engine control module (ECM) with a signal voltage proportional to accelerator pedal movement. The APP sensor 1 signal voltage at the rest position is near the low reference and increases as the pedal is actuated. If the ECM detects that the signal voltage that is more than 4.8 volts, DTC P2123 sets.