Electrical power supply general

Work instructions after disconnecting the battery

Effects of disconnection or total discharge of the battery on electrical systems in the vehicle, subsequent measures:

Never disconnect battery with engine

Never start engine without securely

Never use a boost charger to start the

Whenever possible, use jump leads with

Plug connectors of control modules or other electronic components must never be connected or disconnected with the ignition switched on. Exception: vehicles with the additional equipment M 536 (alarm siren with tilt sensor).

Note concerning M 536:

In order to avoid triggering the alarm siren (installed on right next to the battery) of vehicles with M 536, terminal 86 S of the battery must be disconnected with the ignition on (all loads must be switched off beforehand).

Instrument cluster

The trip counter is set to 0 when the power supply is disconnected.


Depending on the software version, the clock is set to 12:00 a.m. or 1:00 a.m. when the power supply is disconnected.


Enter the current time again. On-board computer

Disconnection of the vehicle battery deletes the memories for average speed and average consumption. As a result, the displayed range on remaining fuel can be markedly different or even 0. The outside temperature indicator loses its memory effect. In other words, the indicated outside temperature can be too high due to the heat radiated when the vehicle is hot.

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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