BMW 7 Series: Service Information

Control Unit Replacement

Teaching in the Luggage Compartment Lid End Stops

If the luggage compartment lid lift control unit has been replaced, a new teach-in procedure will be necessary for the upper end stop. To do this, the luggage compartment lid has to be moved until obstructed by the upper stop.

The obstruction of the luggage compartment lid, and thus the drop-out of the Hall sensor pulses, marks the point at which the luggage compartment lid has reached its maximum opening angle. From this point, a value of approximately 5 % of the total opening angle is deducted. This will be the future opening angle of the luggage compartment lid. This point is also named the soft stop.

The soft stop prevents the luggage compartment lid from opening as far as the end stop and being damaged.

NOTE: The lower end stop is determined by the change in status in the contact switch of the luggage compartment lid lock from open to closed. The junction box electronics send out the status of the luggage compartment lid contact switch on the K-CAN2.

Spindle Drive Replacement

It is necessary to disconnect the plug connections when replacing the spindle drives. To protect the control unit or the spindle drives, terminal 30B should be switched off beforehand.

If the HKL is woken in this situation, it checks whether the spindle drives are connected. If the spindle drives are in fact not connected, a fault code memory entry will be generated. In response to the fault code memory entry, the HKL prevents control of the spindle drives. The automatic luggage compartment lid actuating system does not work, even if the spindle drives are connected now.

The HKL control unit must be allowed to enter sleep mode once more and terminal 30B switched off. The spindle drives are checked again the next time the control unit is woken. If the check is successful, the automatic luggage compartment lid actuating system is switched to active again.

After replacing the spindle drives, closing and opening of the luggage compartment lid must be adapted to given vehicle conditions. The luggage compartment lid lift does not recognize the position of the luggage compartment lid after installing the new spindle drives.

The spindle drives must be taught-in at the vehicle to enable the luggage compartment lid to recognize the position. The corresponding diagnosis order must be carried out for this purpose. This will ensure smooth opening and closing of the luggage compartment lid.

NOTE: The service information does not replace the current information available to Service, nor does it replace repair instructions.

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