Mercedes-Benz 300 SE Operator's Manual page 86

Exterior Lamp Failure Indicator
Lamp
With the key in steering lock position
2, a dim indicator lamp comes on, and
goes out when the engine is running.
With the key in steering lock position 2
or with the engine running, a bright
illumination of this lamp indicates an
exterior lamp failure.
If an exterior lamp fails, the indicator
lamp will come on only when that lamp
is switched on.
If a brake or turn signal lamp fails, the
lamp failure indicator will come on
when applying the brake or actuating the
turn signal and stay on until the engine is
turned off.
Note:
The indicator lamp will also come on if
an incorrect bulb is installed.
If additional lighting equipment is
installed (e.g. auxiliary headlamps etc.)
be certain to connect into the fuse
before the failure indicator monitoring
unit in order to avoid damaging the
system.
Seat Belt Warning Lamp
With the key in steering lock position
2, the warning lamp comes on and an
audible warning sounds for a short
time if the driver's seat belt is not
fastened.
After starting the engine, the warning
lamp blinks for a brief period to
remind the driver and passengers to
fasten seat belts before driving off.
Brake Pad Wear Indicator Lamp
The brake pad wear indicator lamp in
the instrument cluster comes on when
the key in the steering lock is turned to
position 2 and goes out when the
engine is running.
If the indicator lamp lights up during
braking, this indicates that the front
wheel brake pads are worn down (on
vehicles equipped with ASR, it
indicates that the front and/or rear
wheel brake pads are worn down).
Have the brake system checked at your
authorized Mercedes-Benz dealer as
soon as possible.
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