System Description

The cruise control system associated with the gasoline engines includes the following components:
^ The Vehicle Control Module (VCM)
^ The cruise control module
^ The cruise control cable
^ The multifunction lever
^ The brake release switch
^ The clutch release switch (manual transmission) The cruise control module operates in the following manner:
^ The cruise control module contains a stepper motor.

The stepper motor is used to change throttle position.
^ The cruise control module receives commands from the multifunction lever.
^ The cruise control module receives vehicle speed from the VCM.
^ The cruise control module uses the multifunction lever and the VCM in order to control speed.

Brake Release Switch
The cruise control module uses an electronic brake switch which contains one normally open switch contact and one normally closed switch contact. These contacts are part of the zero adjust brake switch. When the brake pedal is depressed, the two brake switch contacts change input states at the cruise control module. The cruise control module then shuts off all the cruise control outputs.

Clutch Release Switch
For vehicles equipped with a manual transmission, the clutch release switch is on the clutch push-rod. When the clutch pedal is depressed, the clutch release switch activates and interrupts the voltage supply to the cruise control circuit in the engine control module, and disengages the cruise module.

Vehicle Speed Signal
The vehicle speed sensor (VSS) generates the vehicle speed signal at the transmission. The VCM translates the VSS.

The VSS mounts to the automatic transmission assembly. The VSS produces an AC signal. The frequency of this signal is proportionate to the transmission output shaft speed. The AC signal goes to the VCM for amplification and conversion to a digital square wave that represents the vehicle speed in terms of pulses per mile (ppm). The VCM provides a 4000 PPM signal.

This 4000-PPM signal is available to the cruise control module, and the speedometer in the instrument cluster.