Function

1st version up to 08/95

Sequence of functions as shown when unlocking the vehicle via the driver door
The electrical switch (SN1) in the lock is operated when the key in the lock cylinder is turned anticlockwise. This switch then conducts a negative voltage to the PSE via its control line.

The PSE (A37) starts up and generates pressure which is led to all pneumatic actuators via a pipeline system. The diaphragms in the actuators are pressed up, operate the locks via linkages and unlock them. The tank flap actuator unlocks the flap directly.

A pressure switch switches off the supply pump if a pressure of approx. 450 mbar is reached in the system.

Now the pneumatic pipeline system and the actuators are depressurized again via the PSE (A37) the system is depressurized and the unlocking process is complete.

The locking process proceeds in a similar way to the unlocking process. However by turning the key clockwise, a second electrical switch (SN2) in the lock is operated. This switch also conducts ground to the PSE (A37) via its control line. The direction of rotation of the pump motor is reversed and thus it generates the vacuum required for locking.



2nd version as of 09/95

Sequence of functions as shown when unlocking the vehicle via the infrared remote central locking (RCL)
Point the remote control with the transmitter output at the receiver in the interior mirror and press transmitter button. The infrared control module can then conduct a negative voltage to the pneumatic system equipment via its control line.

The pneumatic system equipment (A37) starts up and generates excess pressure which is led to all the pneumatic actuators via a system of lines. The diaphragms in the actuators are pressed up, operate the locks via linkages and unlock them. The tank flap actuator unlocks the flap directly.

A pressure switch switches off the supply pump if a pressure of approx. 450 mbar is reached in the system.

Now the pneumatic line system and the actuators are depressurized again via the pneumatic system equipment (A37) - the system is depressurized and the unlocking process is complete.

The locking process proceeds in a similar way to the unlocking process. However the pneumatic system equipment (A37) is actuated to ground by the next actuation of the transmitter button via the second control line of the infrared remote control module. The direction of rotation of the pump motor is reversed, generating the vacuum required for locking.






Function diagram 1st version






Function diagram 2nd version