Mercedes-Benz 2007 G-Class Operator's Manual page 326

Problem
-
The yellow ABS indicator lamp
comes on while driving.
Possible cause/consequence
The charging voltage has fallen below
10 volts. The ABS has switched off.
The battery might not be charged sufficiently.
Practical hints
What to do if ...
Suggested solution
When the voltage is above this value
again, the ABS is operational again and
the ABS indicator lamp should go out.
If the ABS indicator lamp does not go out:
Have the generator (alternator) and
the battery checked.
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