P1125

DTC P1125 Accelerator Pedal Position (APP) System

Circuit Description

The accelerator pedal position (APP) sensor is mounted on the accelerator pedal control assembly. The sensor is made up of two individual sensors within one housing. The APP sensor 1 and APP sensor 2 are hall element type sensors each with the following circuits.

^ 5 volts reference circuit
^ Low reference circuit
^ Signal circuit

The ECM supplies 5 volts to the APP sensor on the 5 volts reference circuit. The ECM also provides a ground on the low reference circuit. The APP sensor provides a signal to the ECM on the signal circuits which is relative to the position changes of the accelerator pedal angle. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed. The APP sensor 2 signal voltage is high at rest and decreases as the pedal is depressed. If the ECM detects one or more APP sensor circuit is open circuit or short circuit this DTC will set. The APP sensor 1 signal voltage and the APP sensor 2 signal voltage are out of the correlation this DTC will also set.

Condition for Running the DTC

^ DTCs P0642 P0643 P0652 and P0653 are not set.

Condition for Setting the DTC

Either of following condition is met:
^ One of two sensor circuit contain an open circuit or a short circuit.
^ The APP sensor 1 and 2 are out of correlation.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type A.
^ The ECM inhibits EGR control.
^ The ECM inhibits DPF regeneration control.
^ The ECM inhibits cruise control.
^ The ECM inhibits PTO control.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the MIL/DTC - Type A.

Diagnostic Aids

^ If an intermittent condition is suspected refer to Intermittent Conditions in this section.

Circuit/System Testing DTC P1125