2000 BMW 328i (E46) Technical Service Bulletin # 840401 Date: 010501
Battery - Disconnecting Procedure With MK3 Nav System
GROUP 84
Phone, Navigation Systems
84 04 01
Woodcliff Lake, NJ
May 2001
Service Engineering
SUBJECT
Battery Disconnecting Procedure on Vehicles with MK3 Nav System
MODEL
E38, E39 with Nav from 09/00
188
E52, E53 with Nav from 10/00
E46 with Nav from 06/00
SITUATION
The MK3 Navigation computer powers down in approximately 60 seconds after the ignition has been turned OFF (red LED on the computer goes
OFF).
If the power supply to the MK3 unit is interrupted (by removing/disconnecting the computer from the vehicle, or by disconnecting the vehicle's
battery) in the time period of 55 to 57 seconds after the ignition has been turned OFF, the power-down procedure ("erase and save data in Non
Volatile RAM") can be corrupted. This will result in a total failure of the MK3 computer (red LED off, CD eject function inoperative, board monitor
screen permanently blank, and no sound from the audio system). In such a case, the navigation computer has to be replaced.
CORRECTION
On vehicles with MK3 navigation system, prior to disconnecting the battery or removing (disconnecting) the Nav computer, make sure the MK3 Nav
computer is in the power-down mode (red LED on the unit is OFF).
WARRANTY INFORMATION
Damaged MK3 Nav computers caused by not following the required power-down procedure are not considered defective and are not warranty
