Principles of Operation
The stoplamp switch is normally closed to ground. When the brake pedal is applied with the speed control system engaged, the stoplamp switch closes (to battery voltage), putting the speed control in stand-by mode.
NOTE:
A redundant brake deactivator, the speed control deactivator switch, is provided as an additional safety feature.
NOTE:
The speed control module is integral to the powertrain control module (PCM).
The clockspring provides the electrical interface between the steering column wiring and the speed control switches in the steering wheel.
The inputs to the PCM for the speed control system are the:
- anti-lock brake (ABS) module
- digital transmission range (TR) sensor
- speed control deactivator switch
- speed control switches
- vehicle speed signal (VSS)
The input to the speed control actuator comes from the PCM.
The output of the speed control actuator is through the speed control cable. The speed control cable then positions the throttle as requested.