Operation CHARM: Car repair manuals for everyone.

Cruise Control: Description and Operation






In contrast to the previous cruise control system, the control unit and actuator element are in one housing.

The cruise control housing is located above the pedals and is attached to the pedal bracket.

The engine throttle is adjusted by a Bowden cable from the cruise control system to the accelerator pedal and a second cable from the accelerator pedal to the throttle.

The play of the Bowden cable is set using an adjustment system integrated in the cable. The specified setting of the Bowden cable is of mutmost importance for the correct functioning of the cruise control system.

Operator switches
The following functions and switch settings are possible:
- System ready/off Main switch (new)
- Set/accelerate Steering-column switch, forward
- Resume Steering-column switch, down
- Decelerate Steering-column switch, down (new)
- Off Steering-column switch, pull
- Tip function, acceleration Steering-column switch, forward
- Tip function, decelerate Steering-column switch, down (new)

Main switch
The system is set to "ready" using a main switch. "Ready" is indicated by a green indicator lamp in the speedometer. The main switch itself is on the steering- column control. If, with 'ignition on", the system has not yet been activated via the main switch, the indicator lamp will light up for 5 seconds as a lamp test.

Set
The system regulates within a speed range of approx. 25 to 125 mph.
When the cruise control has been set, the speed can be increased in steps of approx. 1 mph by repeatedly pressing in the "set" direction.

Resume
The speed last stored is resumed by pressing the operating lever downwards. When the cruise control has been set, the speed can be decreased in steps of approx. 1 mph by repeatedly pressing downward. The vehicle will decelerate if the lever is held in its downward position.

Off
Pulling the operating lever immediately interrupts regulation regardless of the system's operating status. It the lever is held in this position for more than 10 seconds, the main switch is switched off for more than 10 seconds, or the ignition is switched off, the speed last stored is deleted.

Safety concept
The cruise control system is immediately deactivated if:
- the operating level or main switch is moved to the "Off" position.
- the clutch is activated or the drive position "P" or "N" is selected.

New
In contrast to the previous cruise control system, the speed driven last is not automatically resumed after the clutch has been actuated. This prevents the engine from revving if no gear is selected after shifting.

Actuation of brake
New

The brake light switch is a double-contact switch and triggers forced deactivation by means of the following functions:
- The full supply current of the electromagnetic actuator coupling flows via the brake light switch (pin 3). If a wire break occurs or the opener contact of the brake light switch is damaged, regulation is deactivated.
- In addition, + 12 V is applied to the brake lights when the vehicle is braked and to the return line of the actuator element. The brake lamps light up.

If, in the case of a fault, the opener contact does not open when the brake lamp switch is actuated, + 12 V is supplied to the supply and return lines of the actuator element. No current flows and regulation is deactivated.