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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 through circuit RES08 (GN/BN) and the clockspring.
- DTC P0579 (Speed Control Switch Circuit Failure) - may set when the speed control switch circuits are open, shorted to voltage or ground.
- DTC P0581 (Speed Control Switch Circuit Failure) - sets when the speed control switch circuits are open or shorted to voltage.

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


C1-C2:






C2-C4:






C4-C6:






C6-C8:






C8-C10: