Pinpoint Test 1: The Speed Control Is Inoperative
PINPOINT TEST 1: THE SPEED CONTROL IS INOPERATIVE
Normal Operation
The PCM sends a signal through circuit WH to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit GN/BN and the clockspring. When the brake pedal is applied, the stoplamp switch sends a voltage signal to the PCM on circuit VT/WH to deactivate the speed control if engaged.The speed control deactivator switch (part of the stoplamp switch) interrupts circuit 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 clutch pedal speed control deactivator switch, normally closed, supplies a ground signal to the PCM through circuit GN/WH. When the clutch pedal is pressed, the clutch pedal speed control deactivator switch moves to the open position, removing the ground signal from the PCM, which deactivates the speed control. Circuit BK/GN supplies ground to the clutch pedal speed control deactivator switch.
The ABS module monitors brake pressure and also receives the stoplamp switch input from the Smart Junction Box (SJB) along the High Speed Control Area Network (HS-CAN) bus. A fault in the ABS module can disable the speed control system.
Possible Causes
- Wiring, terminals or connectors
- PCM not configured for speed control
- Clutch pedal speed control deactivator switch
- Digital transmission range (TR) sensor
- Speed control deactivator switch
- Speed control switches
- Brake pedal position (BPP) switch
- ABS module
- PCM
Diagnostic Procedure
CAUTION:Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
