P1278

Diagnostic Chart:

Schematic:

The Accelerator Pedal Position (APP) sensor system consists of two independent sensors that read differently scaled values of one another in order to command the throttle butterfly to a particular position. The APP sensor signal circuits are monitored continuously. This DTC will set if APP 1 signal voltage should exceed a calibratable upper limit.

DTC PARAMETERS
This DTC will set when:
^ APP 1 Signal Voltage greater than 4.82 volts
^ Battery Voltage greater than 7 volts
^ Conditions exist for longer than 140 milliseconds

DTC P1278 is a (type A) DTC.

DIAGNOSTIC AIDS
To locate an intermittent problem, use the Scan tool to monitor APP sensor 1 with ignition On, engine Off.

Wiggling wires while monitoring APP sensor 1 may locate the area where a short to voltage exists.