Function of electric steering column control module - GF80.57-P-4103-01A

Unlocking 

When the electric steering column (ESC) control module (N26/5)  receives the command to unlock it first checks the identification. If this check is successful the steering is unlocked mechanically. The auxiliary drive pulls the locking bolt out of the locking ring in the steering shaft. The locking bolt is arrested mechanically twice in the unlocked position. A limit switch indicates the position of the locking bolt to the ESC. The function of the limit switch and double mechanical arrest is checked by the ESC. When the ESC recognizes that the locking bolt is in the unlocked position and the arrest mechanism is functioning properly, it releases the electronic ignition switch (EIS) control module (N73)  via the CAN bus allowing the key to be turned.

Locking 

When the electric steering column (ESC) control module (N26/5)  receives the command to lock it actuates a solenoid. The solenoid releases the mechanical arrest for the locking bolt. The auxiliary drive then moves the locking bolt into the locking ring on the steering shaft. The steering is then locked again.