Normal Operation

WARNING: This page is about a different car, the 2009 Mercury Milan, 2009 Lincoln MKZ, and 2009 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

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. When the brake pedal is applied, the smart junction box (SJB) sends a message to the PCM to deactivate the speed control if engaged.

The speed control deactivator switch (part of the stoplamp switch) interrupts circuit CES09 (VT/OG) removing the voltage signal to the PCM when the brake pedal is applied. This is a redundant signal to the PCM.

Vehicles equipped with a manual transaxle have an additional clutch pedal speed control deactivator switch. The PCM sends a signal through circuit CE904 (GN/VT) to the clutch pedal speed control deactivator switch. The return signal is sent to the PCM through circuit RE407 (YE/VT).

This pinpoint test is intended to diagnose the following:

Wiring, terminals or connectors
PCM not configured for speed control
Stoplamp switch
Clutch Pedal Position (CPP) switch
Speed control switch
Digital Transmission Range (TR) sensor
Vehicle speed signal
PCM