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Actuator

Actuator



The clutch actuator unit is mounted in the engine bay behind the battery.

The clutch actuator unit consists of a housing containing a worm gear with position sensor, a compensating spring and electronic circuitry. The master cylinder and an electric motor are mounted on the actuator. The electric motor is controlled by the electronic circuitry and operates the master cylinder by means of the worm gear.

The actuator unit is powered by a +30 supply from fuse 10 and grounded at grounding point G33P.

Five leads connect the clutch actuator unit to the control module. When the ignition switch is turned to the ON position, the control module activates the clutch actuator unit by applying about 5 V to it from pin 32 and the output stage for the clutch actuator unit's motor by applying about 6 V to it from pin 6. The control module then sends a signal for the requested clutch position to the clutch actuator unit via a two-wire data link (pins 22, 23).

When the actuator unit has moved the clutch to the requested position by means of the electric motor and worm gear position sensor, it sends the current position of the clutch back to the control module which checks that it coincides with the requested position. When the clutch is fully engaged, the control module lowers the voltage on pin 32 and so switches off the actuator motor.

The clutch actuator unit obtains reference ground from pin 17 of the control module. In the event of a fault in the control module, the hydraulic system or the wiring connected to the actuator unit, "CHECK ACS" lights up and the clutch is rendered unserviceable.