Circuit Description
WARNING: This page is about a different car, the 2005 Buick LaCrosse and 2005 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
The accelerator pedal position (APP) sensor 1 and APP sensor 2 are potentiometer type sensors, each with the following circuits:
- A 5-volt reference circuit
- A low reference circuit
- A signal circuit
The control module provides the APP sensors a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 and the APP sensor 2 signal voltages are both low at rest and increase as the pedal is depressed. When the control module detects that the APP sensor 1 and the APP sensor 2 signal circuits are out of correlation, DTC P2138 sets.