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 the ECM decides that the two signal inputs are in disagreement.

DTC P1271 will set if APP 1 and APP 2 provide conflicting data to ECM when:

P1271 is a (type A) DTC.

Using scan tool, monitor APP Sensor 1 and APP Sensor 2 with ignition On, engine Off, and:

1. Accelerator pedal at normal rest position.
2. Accelerator pedal pressed completely to floor.

Voltage should be within 0.1 volts of:

If voltage readings are not as above, replace APP sensor assembly.