Operation CHARM: Car repair manuals for everyone.

Circuit Operation

The Electro-Motor Cruise Control is a speed control system which maintains a desired vehicle speed under normal driving conditions. The system has the capability to CRUISE, COAST, RESUME SPEED, ACCELERATION, TAP-UP and TAP-DOWN.

Depressing the Set and R/A Switches simultaneously will suspend cruise control operation without removing memory speed.

An Electronic Controller and Electric Motor are contained in the Cruise Control Module. The Controller monitors vehicle speed and operates the Electric Motor. In response to the Controller, the motor moves a connecting strap that is attached to the Cruise Control Cable. The Cable moves the Throttle Linkage to vary throttle position in order to maintain the desired cruise speed. The Cruise Control Module contains a low speed limit which will prevent system engagement below a minimum speed, about 25 mph. The module is controlled by mode control switches located on the LH Steering Column, part of the Turn Signal/Headlamp Dimmer Switch/Cruise Control Actuator/Windshield Wiper/Windshield Washer Lever.

With the Ignition Switch in "RUN," battery voltage is applied to terminal "F" of the Cruise Control Module. When the Slider Switch is moved to the "ON" position, battery voltage is applied to terminal "A" of the Cruise Control Module Connector. If the brake pedal is not depressed, battery voltage is present at module terminal "D." If the brake pedal is depressed, battery voltage is present at module terminal "G." The module must see terminal "D" change state once each Ignition cycle. (The brake pedal must be depressed once each Ignition cycle for cruise operation to occur). (Some Cruise Modules will use either terminal "D" or "G"). With the brake pedal not depressed, terminal "0" must see current flow through CKT 17 for cruise to operate properly. When the Slider Switch is moved to the "R/A" position, battery voltage is applied to terminal "C" of the module. With the Set Switch depressed, battery voltage is present at module terminal "B." Cruise Control Module Connector terminal "K" is the speed signal terminal. In operation, voltage will oscillate between a high of 4 to 5 volts and a low of near ground. Cruise Module terminal "H" is not used. Ground is at module terminal "E."