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12 00... Instructions for disconnecting and connecting battery: Notes

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.
IMPORTANT:
  • There is a danger of mixing up battery leads: 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 stored stations and restore them after connecting the battery.
  • Stored settings of the on-board computer and clock will also be lost.
  • All available central keys must be re-coded for cars with first generation infrared transmitter locking systems.

General notes on disconnecting battery: 

After connecting battery: 

IMPORTANT: After a power supply interruption some equipment is disabled and must be reactivated.
Likewise, individual settings are lost and must be activated.
Example:
  • Activate sliding sunroof
  • Vehicles with AFS only: Activate steering angle
  • If necessary, activate power windows
  • If necessary, activate mirror with compass

For further information and instructions on vehicle-specific activation, please refer to the point " " under the document type " " from the IDC (index number 11).