Test C: Speed Control Switch Stuck Or Circuit Failure

PINPOINT TEST C: SPEED CONTROL SWITCH STUCK OR CIRCUIT FAILURE

C1-C2:

C2-C4:

C4-C6:

C7-C8:

C9-C11:

C11-C13:

Normal Operation
The PCM sends a reference voltage signal, which passes through the clockspring and through circuit 151 (LB/BK) to the speed control switches. The speed control switch signal return (ground) is provided by circuit 848 (DG/OG) through the clockspring.
- DTC P0579 (Cruise Control Multi-Function Input A Circuit Range/Performance) - may set when the speed control switch is stuck or the switch circuits are open, shorted to voltage or shorted to ground.
- DTC P0581 (Cruise Control Multi-Function Circuit High) - 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