Display messages Possible causes/consequences and
M Solutions# The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 175).
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do
not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. 4
Check Engine Oil
At Next Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X
Check the oil level when next refueling, at the latest
(Y page 330).
X If necessary, add engine oil ( Y page 330).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
www.mbusa.com (USA only). Display messages
259
On-board computer and displays Z
necessary for you to disconnect the battery
yourself, make sure that:
R
you
switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic
system may be damaged.
R in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The
vehicle is secured against rolling away.
You can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
In order for the battery to achieve the
maximum possible service life, it must always
be sufficiently charged.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop. You can also charge the battery
with a charger recommended by Mercedes-
Benz. Contact a qualified specialist workshop
for further information.
Have the battery charge level checked more
frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for
a lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
i Remove the SmartKey if you park the
vehicle and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power. i
If the power supply has been interrupted,
e.g. if you reconnect the battery, you will
have to:
Rset the clock. Information on setting the
clock can be found in the separate
operating instructions.
On vehicles with COMAND and a
navigation system, the clock is set
automatically.
R reset the function for folding the exterior
mirrors in/out automatically, by folding
the mirrors out once ( Y page 114). Charging the battery
G
WARNING
Never charge a battery still installed in the
vehicle
unless a battery charger unit approved
by Mercedes-Benz is being used. Gases may
escape during charging and cause explosions
that may result in paint damage, corrosion or
personal injury.
A battery charger unit specially adapted for
Mercedes-Benz vehicles and tested and
approved by Mercedes-Benz is available as an
accessory. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for further
information and availability.
Charge the battery in accordance with the
separate instructions for the battery charger. G
WARNING
There is a risk of acid burns during the
charging process due to the gases which
escape
from the battery. Do not lean over the
battery during the charging process. G
WARNING
Battery acid is caustic. Avoid contact with the
skin, eyes or clothing.
! Only use battery chargers with a
maximum charging voltage of 14.8 V. 350
Battery (vehicle)
Breakdown assistance