Test A: The Speed Control Is Inoperative
PINPOINT TEST A: THE SPEED CONTROL IS INOPERATIVEA1-A3:
A3-A6:
Normal Operation
The powertrain control module (PCM) sends a signal through circuit 248 (TN/OG) to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit 133 (BK) 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 interrupts circuit 535 (LB/RD), removing the voltage signal to the PCM, when the brake pedal is applied firmly and passes the stoplamp switch trip point. This is a redundant signal to the PCM.
Possible Causes
- Speed control switch
- Digital transmission range (TR) sensor
- PCM