Cruise Control Functional Switches

Cruise control system uses the cruise control module assembly to maintain desired vehicle cruise speed and operation. Cruise control module assembly has a controller and an electric stepper motor to vary the throttle in each different cruise control mode. Controller monitors vehicle speed and operates stepper motor. Stepper motor operates in response to controller, to maintain desired cruise speed. Electric stepper motor moves a strap that is attached to cruise control cable which moves throttle linkage. Cruise control module assembly contains a low speed limit which will prevent system engagement below a minimum speed of 25 MPH. Module assembly is not serviceable.

Operation of the controller is controlled by function control switches located on the steering wheel. Cruise control functional control switches include ON/OFF, SET/COAST, R/A (resume/accelerate). Switches provide driver control of the cruise control system. Cruise control release switch and stoplamp switch are used to disengage cruise control. A release switch assembly and a stoplamp switch assembly are mounted on brake pedal bracket. Cruise control system disengages when driver presses brake pedal. Speed of vehicle at brake actuation will be stored in memory of cruise module. When driver turns on/off switch or ignition switch off, cruise control turns off. Vehicle speed stored in memory of cruise module will be lost.

Ignition 1 voltage is supplied from cruise control fuse to cruise control module. Cruise control module is grounded to chassis. When cruise control ON/OFF switch is on, ignition 1 voltage is applied to cruise control on switch signal circuit of cruise control module. If driver has not pressed brake pedal, ignition 1 voltage is supplied through ABS/TCC switch, to TCC Brake switch signal circuit of cruise control module. When driver presses brake pedal, battery positive voltage is supplied from stop lamp fuse through closed stop lamp switch to stop lamp switch signal circuit of cruise control module. When SET/COAST button is pressed , ignition positive voltage is applied to cruise control set/coast switch signal circuit of cruise control module. When pressing R/A (resume/accelerate), ignition positive voltage is applied to cruise control resume/accelerate switch signal circuit of cruise control module.

Cruise control module receives a vehicle speed signal input from Powertrain Control Module (PCM). In operation, voltage varies between zero volts and 5 volts. Cruise control module, cruise engaged circuit, sends a signal to PCM when cruise is engaged. Cruise control module, cruise inhibit signal circuit is a circuit used by PCM to disengage cruise control when conditions inconsistent with cruise operation exist. After cruise control engaged criteria has been met and cruise ON and Set/Coast have been commanded, cruise control module sends a signal to PCM that cruise control is engaged.

PCM will inhibit cruise control under the following conditions:

• When vehicle speed is less than 25 MPH.
• When PARK, REVERSE, NEUTRAL, or 1st gear is indicated.
• With low engine RPM.
• With high engine RPM (fuel cut-off).
• When vehicle speed is too high.
• When an over or under charged battery voltage condition exists.
• Anti-lock brake system/traction control system is active for more than 2 seconds.
• A 6 MPH or more decrease in non-drive wheel speed in 0.4 seconds with out seeing the extended brake travel contacts of the TCC/Brake switch transition.

If PCM determines that any cruise control inhibit conditions exist, PCM will disengage cruise control. PCM accomplishes this by opening cruise control inhibit signal circuit.

Monte Carlo uses 2 steering wheel-mounted switches: a cruise control ON/OFF switch and an integrated SET/COAST/RESUME/ACCEL switch. All other models use ON/OFF, RESUME/ACCEL and SET/COAST functional switches located on multifunction lever on steering column. Switch functions are described as follows:

1. OFF
   
   System disengages when cruise control switch is turned off.
2. ON
   
   System is ready to be set when cruise control switch is turned on.
3. RESUME/ACCEL (R/A)
   
   RESUME/ACCEL (R/A) switch will not initially set cruise speed, but when cruise has been disengaged by braking, pushing this switch will cause cruise to resume previously set speed. This is the resume function. Vehicle speed must exceed 25 MPH at time of activation in order for cruise control operation to return to last cruise speed setting. Accelerate function occurs when RESUME/ACCEL (R/A) switch is held in position for more than one second. This causes the vehicle to accelerate until switch is released. When released, system maintains new set speed. Vehicle speed must exceed 25 MPH at time of activation in order for cruise control operation to return to last cruise speed setting. Also, by quickly pressing and releasing (tapping) this switch, the set speed is "tapped-up" in one MPH increments.
4. SET (Except Monte Carlo)
   
   The SET switch, located on end of multifunction lever, engages cruise control. To set cruise speed, turn cruise control system on and use accelerator to get up to desired speed. Push and release SET switch and remove foot from accelerator. Desired speed is maintained. During engagement, if SET switch is pressed and held, vehicle decelerates (cruise disengages) until switch is released. When switch is released, cruise engages and maintains new set speed. Also, by quickly pressing and releasing (tapping) this switch, the set speed is "tapped-down" in one MPH increments.
5. SET/COAST (Monte Carlo)
   
   SET/COAST switch engages cruise control. To set cruise speed, turn cruise control system on and use accelerator to get up to desired speed. Push and release SET switch and remove foot from accelerator. Desired speed is maintained. During engagement, if SET/COAST switch is pressed and held, vehicle decelerates (cruise disengages) until switch is released. When switch is released, cruise engages and maintains new set speed. Also, by quickly pressing and releasing (tapping) this switch, the set speed is "tapped-down" in one MPH increments.