Sedan

Central Locking Components:

Central Locking Diagrams:

Locations of components

22A Fuse holder
In the electrical distribution box, in the engine compartment, on the left-hand wheel housing

57 3-pole connector
One in the left-hand front door
One in the engine compartment, at the upper hinge of the left-hand front door, behind the electrical distribution box

57R 3-pole connector
One in the right-hand front door
One in the engine compartment, at the upper hinge of the right-hand front door

59 2-pole connector
One in the right-hand front door
One in the engine compartment, at the upper hinge of the right-hand front door
One in the left-hand rear door
One in the right-hand rear door
One in the luggage compartment lid, near the motor for the luggage compartment lock
One in the luggage compartment, above the left-hand wheel housing

59R 2-pole connector
One in the left-hand front door
One in the engine compartment, at the upper hinge of the left-hand front door, behind the electrical distribution box

117 Earthing point
Between the ignition switch and the handbrake lever

123 4-pole connector
One in the left-hand B pillar
One in the right-hand B pillar

152A 29-pole white connector
In the electrical distribution box in the engine compartment, on the left-hand wheel housing. The connector is accessible from the interior of the car.

175 Control unit for the central locking system
Under the fascia on the right-hand side, behind the knee shield

183 Key switch for the driver's central door lock
In the driver's door

184 Motor for the co-driver's door lock
In the co-driver's door, at the rear, under the lock

185 Motor for the right-hand rear door lock
Under the lock in the right-hand rear door

186 Motor for the left-hand rear door lock
Under the lock in the left-hand rear door

188 Motor for the tailgate lock
In the tailgate

Operation
The central locking system of the car locks or unlocks all doors and the luggage compartment lid when the key is turned in the lock of the driver's door.

Terminal 4 of control unit 175 for the central locking system is continuously supplied from fuse 24, via white 29-pole connector 152A. The control unit is controlled by key switch 183 in the driver's door.

When the driver's door is locked, terminal 1 of the control unit will be earthed via earthing point 117.

Current will then flow from output 8. All central locking motors (which are connected in parallel) will now be energized for approx. 1 second and the doors will be locked. The motors are earthed through pin 7 of the control unit, and on from terminal 3 to earthing point 117.

When the driver's door is unlocked, terminal 2 of the control unit will instead be earthed across the key switch. The motors will now be energized from pin 7 instead, and will be earthed across pin 8 of the control unit (for approx. 1 second), causing the locks to open.

On right-hand drive cars, the key switch is connected to connector 57R, and motor 184 for the co-driver's door lock is connected to connector 59R.

Fault-tracing hints

1. Check fuse 24 and check that the supply to it is live.

2. Check that the supply to terminal 4 of control unit 175 is live.

3. Check that pin 7 of the control unit is live when the doors are being unlocked and that pin 8 is live when the doors are being locked.

Note that terminals 7 and 8 are only energized for around one second in conjunction with locking and unlocking. Measurement at these terminals must therefore be carried out when key switch 183 is switching over.

4. Check the connectors, cable harnesses and earth connections.

Note
On testing, the actuating motors may be connected to terminals 7 and 8 of the control unit only. Do not connect them to any other power supply sources. Doing so may overload the motors and damage them.