Mercedes-Benz 2003 M-Class Operator's Manual page 266

Practical hints
Jump starting
Let the engine of the assisting vehicle
run at idle speed.
Connect the negative terminals 3 of
the batteries with the jumper cables.
Start with the charged battery.
Start the engine of the disabled vehi-
cle.
266
Now you can again turn on the electrical
consumers. Do not turn on the lights under
any circumstances.
Remove the jumper cables first from
the negative terminals 3 of the batter-
ies and then from the positive
terminals 1.
Have the battery checked at the
nearest authorized Mercedes-Benz
Center.
i
The vehicle cannot be started via
tow-start.