Electronic cruise control is a speed control system. The system maintains a desired vehicle speed under normal driving conditions. However, steep grades up or down may cause variations in the selected speeds. The electronic cruise control system has the capability to perform the following functions:

The main parts of the cruise control system are:

The cruise control system uses a cruise control module assembly in order to obtain the desired vehicle cruise operation. The following two important components in the module help to perform this operation:

The controller monitors the vehicle speed. The controller operates the electronic stepper motor. The motor moves a band and throttle linkage, in response to the controller, in order to maintain the desired cruise speed. The cruise control module assembly contains a low speed limit. The low speed limit prevents system engagement below a minimum of 40 km/h (25 mph). Functional control switches on the multi-function turn signal lever control the operation of the controller.

The cruise control release switch assembly and the stoplamp switch assembly disengage the cruise control system. The switch assemblies are mounted on the brake pedal bracket assembly. When the brake pedal assembly is depressed, the cruise control system electronically disengages. The throttle returns to the idle position. The system disengages by the activation of the brake cut-out input to the cruise control module assembly. At the point when the driver applies the brakes, the system memory stores the speed of the vehicle.

Vehicle Speed Sensor (VSS) Buffer Assembly

The vehicle speed sensor (VSS) buffer assembly receives a signal from the VSS (permanent magnet generator). The signal indicates the speed of the vehicle. The VSS buffer assembly processes this signal and supplies the signal to the following:

Vehicle Speed Sensor (VSS)

The vehicle speed sensor is mounted on the transmission assembly. The VSS produces an AC signal. The frequency of the signal is proportional to the rotation speed of the transmission assembly output shaft. The rotation speed is proportional to the speed of the vehicle.

The VSS buffer amplifies and converts the AC signal which the VSS produces. The VSS buffer assembly supplies the signal to the following components:

The VSS buffer opens and closes internal solid state switches to ground in order to produce the signal.

The signal reaches the cruise control module and the speedometer assembly at a rate of 4000 pulses per mile.

The PCM converts the signal to 4000 pulses per mile. The control module and speedometer assembly internally convert the number of pulses per mile to pulses per second to determine vehicle speed.