Mercedes-Benz 2002 M-Class Operator's Manual page 277

Instruments
Operation
and controls
Battery
Therefore, we strongly recommend that you have the
battery charge checked frequently, and corrected if
necessary, especially if you use the vehicle less than
approximately 200 miles (300 km) per month,
mostly for short distance trips, or if it is not used for
long periods of time.
Only charge a battery with a battery charger after the
battery has been disconnected from the vehicle's
electrical circuit.
Always disconnect the battery negative lead first and
connect last.
When removing and connecting the battery, always
make sure that all electrical consumers are off and the
key is in steering lock position 0. The battery must
always be securely installed when the vehicle is in
operation. During removal and installation always
protect the disconnected battery positive (+) terminal
with the cover attached to the battery.
While the engine is running the battery terminal clamps
must not be loosened or detached, otherwise the
generator and other electronic components would be
damaged.
Instrument
Driving
cluster display
274
Practical hints Car care
Note:
The gear selector lever will remain locked in
position "P" and the electronic key cannot be turned in
the steering lock if the vehicle battery is disconnected
or discharged.
After reconnecting the battery also set the clock in
instrument cluster (see page 87), set date in trip
computer (see page 89), resynchronize the sliding/pop-
up roof (see page 294) and the electronic stability
program (ESP) (see page 224).
Battery recycling
Batteries contain material that can harm the
environment with improper disposal.
Large 12 Volt storage batteries contain lead.
Recycling of batteries is the preferred method of
disposal.
Many states require sellers of batteries to accept old
batteries for recycling.
Technical
Index
data