Test C: DTC P0579 Or DTC P0581 - Speed Control Switch Circuit Failure

PINPOINT TEST C: DTC P0579 OR DTC P0581 - SPEED CONTROL SWITCH CIRCUIT FAILURE

Normal Operation
The PCM sends a signal through circuit VES10 (WH) to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit RES08 (GN/BN) and the clockspring.

DTC P0579 may set when a speed control switch is stuck or the switch circuits are open, shorted to voltage or shorted to ground.

DTC P0581 sets when the speed control switch circuits are shorted to voltage or open.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Clockspring
- Speed control switch
- PCM

C1:

C1-C3:

C3-C5:

C5-C6:

C7-C9:

C9-C10: