General information and safety precautions (BMW 3 Series E46)

The engine electrical equipment includes all components of the ignition systems - as part of the electronic digital engine management system DME/BOSCH-MOTRONIC (gasoline engines), preheating (diesel engines), starting and charging. Since these components are functionally related to those that directly ensure the operation of the engine, they are considered separately from the components of the on-board electrical equipment, such as lighting devices, control devices, etc.

When working with electrical equipment, certain safety precautions must be observed:

a) Be careful - electrical appliances are particularly susceptible to damage if not handled correctly during testing, connection and maintenance.

b) Do not leave the ignition on for a long time with the engine off.

c) Do not touch or disconnect spark plug wires while the engine is running or the starter is engaged (gasoline engines).

d) People with a pacemaker should not work with the electronic ignition system (gasoline engines).

e) Never disconnect the battery cables while the engine is running.

f) When connecting the wires from the auxiliary power source for emergency engine starting, observe the polarity.

g) Always disconnect the negative battery cable first and connect it last to avoid short circuits if accidentally touched with a tool while loosening/tightening the terminal clamp.

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