Instructions For Disconnecting and Connecting Battery

Instructions For Disconnecting And Connecting Battery

Observe safety instructions for handling vehicle battery.

Before disconnecting battery:
Switch off ignition.

NOTE: If the ignition is not turned off when the battery is disconnected, fault memories may be set in some control units.

CAUTION:
- Danger of mixing up: If the battery positive and negative leads are the same color and you are in doubt, follow the polarity to the battery, then mark and cover the leads.
- On vehicles with radio code: After disconnecting the battery, the radio code must be re-entered. Therefore obtain the radio code card from the customer beforehand. Note down programmed stations and store these stations back in memory once the battery has been reconnected.
- Stored settings of the on-board computer and clock will also be lost.
- All available keys must be recoded for cars with first generation infrared transmitter locking systems.

General notes on disconnecting battery:
- The battery and the leads to the alternator and starter motor must not be disconnected while the engine is running.
- Detach terminal of battery negative lead from car battery and second battery if fitted. Cover battery negative terminal(s).
- When work is carried out on the electrical system, faults may be caused in the fault memories of some control units when the battery is connected.

After connecting battery:

CAUTION: Required in various models:
- E36 only: Initialize power window
- Initialize sunroof