34 50 000 - ABS indicator lamp - function and test < 34 - Brakes < BMW 728 - 745i
 
From model '83 DESCRIPTION OF AND CHECKING ABS INDICATOR LAMP

The ABS indicator lamp comes on after turning
on the ignition. The indicator lamp should
go out again when the engine is started, if the
ABS is okay.

These procedures are repeated each time the
ignition is turned off and on.

The cause for erroneous indication (indicator
lamp doesn't come on, doesn't go out or comes
on while driving - even occasionally) can be
found with the help of a BMW service test unit
and a brake test stand (dynamometer).

The control unit will automatically switch to
"normal braking" when there is an electric or
electronic defect in the ABS. This means the
car can still be braked, but without control
(the wheels could lock!). The defective system
will be indicated by a continuously burning
ABS indicator lamp in the instrument panel.

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