Cruise Control System
The Cruise Control system consists of the following components and signals:^ Cruise Control system control module 508
^ Cruise Control selector switch 141
^ Pedal switches 133 (manual) and 134
^ Brake light switch 29
^ Speed signal from ABS control module 547
^ Cruise Control signal, active, to the engine management system
Control Module 508
The control module incorporates an electric stepping motor which, depending on the speed of the car, mechanically pulls or releases the cruise control cable connected to the throttle body.
Current (+54 circuit) is supplied to terminal F of the control module and switch 141 via fuse 22.
The control module is connected to grounding point G33P via terminal E.
The speed signal is obtained from the ABS control module via the left-hand front wheel.
The Cruise Control system will not be operative at speeds below 32 km/h (20 mph) or above 220 km/h (137 mph).
Selector Switch 141
The Cruise Control system is controlled by means of selector switch 141. This switch is spring-loaded, i.e. it returns to the neutral position after it has been actuated.
The different positions of the selector switch are:
NEUTRAL POSITION: In the neutral position no current is supplied to any of the terminals A, B and C.
TIP: A TIP position is provided on the left-hand side between the neutral position and the ON/OFF position.
When the Cruise Control system is activated (ON position) and the cruise control is operating, the CRUISE lamp goes out as acknowledgment that the selector switch has been moved to the TIP position.
The CRUISE lamp lights up again when the selector switch springs back to the neutral position.
In the TIP position, current is supplied to terminals B and C of the control module and the Cruise Control system is disengaged.
ON/OFF: The ON/OFF position is to the far left of the neutral position.
In the ON/OFF position current is supplied to terminals A, B and C of the control module.
It any of the terminals is not supplied with current, ON/OFF will not be operative.
RES/- : Current is supplied to terminal C of the control module. There are three functions in this position:
1. When the Cruise Control system is turned on and the cruise control memory is empty, this position can be used as a SET function, i.e. the current speed is stored in the memory.
2. After activation of the brake and/or clutch pedal, the Cruise Control can be restored to the original speed by pressing RES/-.
3. If the button is left in the RES/- position for a prolonged period, speed will gradually be reduced. The new speed will be stored in the memory when the button is released. If the button is pressed briefly, speed will be reduced in steps of 1.6 km/h (1 mph).
SET/+ : On the end of the direction indicators stalk is a spring-loaded SET/+ button. When this button is pressed, current is supplied to terminal B of the control module. This button controls two functions:
4. When the Cruise Control system is operative and the SET/+ button is pressed, the current speed will be stored in the cruise control memory.
5. If the SET/+ button is actuated for a prolonged period, speed will gradually increase. The new speed will be stored in the memory when the button is released. If the button is pressed briefly, speed will increase in steps of 1.6 km/h (1 mph).
Pedal Switches 133 and 134
When the brake or clutch pedal is depressed, the pedal switches will interrupt the supply of current to terminal D of the control module, causing the Cruise Control to be disengaged.
Brake Light Switch 29
When the brake pedal is depressed, brake lights switch 29 closes and terminal G of the Cruise Control system control module is supplied with a positive voltage via fuse 12.
Unless terminal G is grounded via the brake light lamps, the Cruise Control system will not be operative.
Cars With TCS
When the car is equipped with the Traction Control System (TCS), positive voltage from the brake lights switch is supplied to terminal G of the control module for the Cruise Control system via TCS control module 507. This is so that the TCS control module can disengage the Cruise Control if wheelspin occurs.
CRUISE Indicator lamp
The main instrument display panel incorporates a CRUISE indicator lamp which comes on when the Cruise Control system is engaged. This lamp is supplied with current from terminal H of the control module.
In the TIP position, however, the lamp goes out to acknowledge that the switch has been moved to the TIP position. The CRUISE lamp is used to provide information on the system in connection with fault diagnosis.
Automatic Transmission
The Cruise Control system is supplied with current via fuse 9 and switch 76 in selector lever position sensor 239 and also via fuse 22. As a result, the system will not be operative until the selector lever is moved to one of the drive positions (D, 3, 2,1).
Cars With Trionic
On cars equipped with the Trionic engine management system, Turbo and Cruise Control, Trionic control module 430 receives a signal from terminal I of the control module for the Cruise Control system advising it that the system is engaged. This results in smoother adjustment of the car's speed.