Circuit Description

The accelerator pedal position (APP) sensor 1 is a potentiometer type sensor with the following three circuits:

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

The control module provides the APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensor then provides the control module a signal voltage proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 1 signal or the APP sensor 2 5-volt reference voltage is outside the predetermined range, or the APP sensor 1 voltage is lower than a specified value when the accelerator pedal is in the closed throttle position, DTC P2120 sets.