Diagnostic Aids

There are no driveability issues associated with the APP module unless a DTC is present. The most likely causes of this DTC are poor connections or the sensor. The least likely is a PCM problem.

An intermittent may be caused by the following:

• Poor connections
• Rubbed through wire insulation
• Broken wire inside the insulation

A scan tool reads the APP 1 position in volts. It should read about 0.45-0.95 volt with the throttle closed and the ignition ON or at idle. The voltage should increase at a steady rate as the throttle is moved toward wide open throttle (WOT). Also, 90 percent pedal travel is acceptable for correct APP operation. Scan the APP 1 sensor while depressing the accelerator pedal with the engine off and the ignition ON. Display should vary from about 0.74 volt when the throttle is closed to over about 3.7 volts when the throttle is held at wide open throttle (WOT). The following chart will check voltages on all APP circuits to see if they fall in normal ranges. The PCM compares pre-scaled voltages (these are voltages that the scan tool cannot read). The scan tool reads only output voltages.

An intermittent may be caused by any of the following conditions:

• A poor connection
• Rubbed through wire insulation
• A broken wire inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to TESTING FOR ELECTRICAL INTERMITTENTS .

If a repair is necessary, then refer to WIRING REPAIRS or CONNECTOR REPAIRS .