Diagnostic Overview - S/C Switch
The S/C Switch performs diagnostics on the internal signal circuits. If a fault is detected the S/C Switch reports the fault to the SCCM over the LIN Bus circuit. If a speed control fault is present, verify that the switch has the proper Battery feed, ground and a good LIN Bus connection between the switch and SCCM or BCM depending on vehicle. If the circuits test good, the switch is the most likely cause of the DTC.