Cruise Control Description and Operation W/ETC

Cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions. However, steep grades may cause variations in the selected speeds. The electronic cruise control system has the capability to CRUISE, COAST, RESUME SPEED, ACCELERATE, and TAP-UP or TAP-DOWN.

The main parts of the cruise control system are:

The cruise control system uses the TAC module to maintain the desired vehicle cruise speed and operation. The TAC and the powertrain control module (PCM) communicate together to vary the throttle opening in each different cruise control mode. The PCM monitors vehicle speed and operates the throttle actuator. The throttle actuator operates in response to the TAC module, to maintain the desired cruise speed. The throttle actuator motor moves the throttle blade. The PCM assembly contains a low speed limit which will prevent system engagement below a minimum speed of 40 km/h (25 mph). The TAC or PCM module assembly are not serviceable.

The operation of the TAC module is through the function control switches located on the multifunction turn signal lever. The cruise control function control switches includes the ON/OFF, SET/COAST, R/A (resume/accelerate). The switch assembly provides driver control of the cruise control system.

The multiple function stop lamp switch or CPP switch if equipped, is used to disengage the cruise control. A cruise control release switch circuit and a stoplamp switch circuit are used. The stop lamp and CPP switches are mounted to the brake pedal bracket . To disengage the system the driver presses the brake pedal or clutch pedal, if equipped. The speed of the vehicle at brake actuation will be stored in the memory of the TAC module.

With cruise control, the vehicle can maintain a speed of about 40 km/h (25 mph) or more without keeping your foot on the accelerator. When the driver turns off the cruise control ON/OFF switch or ignition switch, the cruise control turns off. The vehicle speed stored in the memory of the TAC module will be lost.

Ignition positive voltage is supplied from the IGN E fuse, to the TAC module. The TAC module is grounded to the chassis. When the cruise control ON/OFF switch is on, ignition positive voltage is applied to the cruise on switch signal terminal of the TAC module. If the driver has not pressed the brake pedal or clutch pedal if equipped, ignition positive voltage is supplied through the switches, to the cruise control brake pedal switch signal and clutch signal, if equipped, terminals of the PCM. Cruise control is canceled when the driver presses either the brake pedal or clutch pedal, if equipped. The stop lamp switch closes, applying battery positive voltage to the stop lamp signal circuit of the TAC module. Voltage is also removed from the brake pedal signal circuit and the clutch switch signal circuit, if equipped, at the PCM. When pressing the SET/COAST button on the multifunction turn signal lever, ignition positive voltage is applied to the set/coast switch signal terminal of the TAC module. When pressing the R/A (resume/accelerate) on the control switch, ignition positive voltage is applied to the resume/accelerate switch signal terminal of the TAC module.

When the cruise switch is in the ON position, and the driver presses the SET/COAST button, the TAC module notifies the PCM that the cruise control is requested. The PCM then checks to see that the cruise control enable criteria is met. If the cruise control criteria has been met the PCM sends a class 2 message to the instrument panel cluster (IPC) to illuminate the cruise light, if equipped

The PCM will inhibit cruise control:

If the PCM determines that any of the cruise control inhibit conditions are present, the PCM will disengage the cruise control. The PCM accomplishes this through data communication with the TAC module. If the PCM disables the cruise control for an inhibiting event it will record the reason for disengagement in the Disengage Definition data file.

Cruise Control Description and Operation Diesel

Cruise control is a speed control system that maintains a desired vehicle speed under normal driving conditions. However, steep grades may cause variations in the selected speeds. The electronic cruise control system has the capability to CRUISE, COAST, RESUME SPEED, ACCELERATE, and TAP-UP or TAP-DOWN.

The main parts of the cruise control system are:

The cruise control system uses the PCM to maintain the desired vehicle cruise speed and operation by varring the injection pump timing. The PCM assembly contains a low speed limit which will prevent system engagement below a minimum speed of 40 km/h (25 mph). The TAC or PCM module assembly are not serviceable.

Cruise control operation is controlled through the function control switches located on the multifunction turn signal lever. The cruise control function control switches includes the ON/OFF, SET/COAST, R/A . The switch assembly provides driver control of the cruise control system.

The stop lamp switch or CPP switch if equipped, is used to disengage the cruise control. A cruise control release switch circuit and a stop lamp switch circuit are used. The stop lamp and CPP switches are mounted to the brake pedal bracket . To disengage the system the driver presses the brake pedal or clutch pedal, if equipped. The speed of the vehicle at brake or clutch pedal actuation will be stored in the memory of the PCM.

With cruise control, the vehicle can maintain a speed of about 40 km/h (25 mph) or more without keeping your foot on the accelerator. When the driver turns off the cruise control ON/OFF switch or ignition switch, the cruise control turns off. The vehicle speed stored in the memory of the PCM will be lost.

Ignition positive voltage is supplied from the Cruise fuse, to the cruise control switch. When the cruise control ON/OFF switch is on, ignition positive voltage is applied to the cruise on switch signal terminal of the PCM. If the driver has not pressed the brake pedal or clutch pedal if equipped, ignition positive voltage is supplied through the switches, to the cruise control brake pedal switch signal and clutch signal, if equipped, terminals of the PCM. Cruise control is canceled when the driver presses either the brake pedal or clutch pedal, if equipped. The stop lamp switch closes, applying battery positive voltage to the stop lamp signal circuit of the PCM. Voltage is also removed from the brake pedal signal circuit and the clutch switch signal circuit, if equipped, at the PCM. When pressing the SET/COAST button on the multifunction turn signal lever, ignition positive voltage is applied to the set/coast switch signal terminal of the PCM. When pressing the R/A on the control switch, ignition positive voltage is applied to the resume/accelerate switch signal terminal of the PCM.

When the cruise switch is in the ON position, and the driver presses the SET/COAST button, the PCM then checks to see that the cruise control enable criteria is met. If the cruise control criteria has been met the PCM sends a class 2 message to the instrument panel cluster (IPC) to illuminate the cruise light, if equipped

The PCM will inhibit cruise control:

If the PCM determines that any of the cruise control inhibit conditions are present, the PCM will disengage the cruise control. If the PCM disables the cruise control for an inhibiting event it will record the reason for disengagement in the Disengage Definition data file.