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Display messagesPossible causes/consequences and M Solutions?The engine fan is defective.XAt coolant temperatures under 248 ‡ (120 †), drive to the next
qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.#The battery is not being charged.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronicsXPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is OK:
XVisit a qualified specialist workshop.The battery voltage is too low.XSwitch off electrical consumers that are not required.XHave the battery and alternator checked at a qualified specialist
workshop.The battery has been charged or the vehicle has been jump-
started.XHave the battery and alternator checked at a qualified specialist
workshop.4
Check oil level at
next gas stationThe engine oil level has dropped to a critical level.XCheck the oil level ( Y page 215).XIf necessary, add engine oil ( Y page 216).XHave the engine checked for leaks if you need to add engine oil
more often than usual.You have added too much engine oil. There is a risk of damaging
the engine or catalytic converter.XSiphon off excess engine oil until it is at the specified level.
Observe the legal requirements.176Display messagesOn-board computer and displays
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Safety systemsProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running.GRisk of accident
ABS (Anti-lock Brake System) is deactivated due to a malfunction.
BAS (Brake Assist), ESP ®
(Electronic Stability Program), EBD
(Electronic Brake force Distribution) and 4ETS are also temporarily
unavailable.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available.
!
The yellow ABS warning
lamp is lit while the
engine is running.GRisk of accident
The on-board voltage is too low. ABS has been deactivated due to
undervoltage.
ESP ®
, BAS, EBD and 4ETS are also therefore deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XSwitch off consumers that are not required, e.g. the rear window
defroster or interior lighting.
ABS will be available again as soon as the vehicle's on-board
electrical system voltage increases.
If the warning lamp is still on:
XHave the battery and alternator checked at a qualified specialist
workshop.!
The yellow ABS warning
lamp is lit while the
engine is running.You have engaged the differential locks. ABS, BAS, EBD, ESP ®
and
4ETS have been deactivated.XDisengage the differential locks.
ABS, BAS, EBD, ESP ®
and 4ETS are subsequently reactivated.Warning and indicator lamps in the instrument cluster185On-board computer and displaysZProCarManuals.com
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GWarning
Failure to follow these instructions can result
in severe injury or death.
Never lean over batteries while connecting.
You might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
GWarning
Do not place any metal objects on the battery
as this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First, touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! Switch off the engine and remove the
SmartKey before disconnecting the
terminal clamps from the battery. You may
otherwise destroy electronic components,
such as the alternator.
! Like other batteries, the vehicle battery
may discharge over time if you do not use
the vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center. You can also charge the
battery with a charger recommended by
Mercedes-Benz. Contact an authorized
Mercedes-Benz Center for further
information.
The battery, breather hose and cover of the
positive terminal clamp must be installed
securely during operation.
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.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing, charging or replacing. Always have
this work performed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
i If the power supply has been interrupted,
e.g. if the battery has been reconnected,
you must carry out the following tasks:
R reset the head restraints on the front
seats ( Y page 80).
Charging the battery
GWarning
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge 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.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge the battery in accordance with the
separate instructions for the accessory
battery charger.
236BatteryRoadside Assistance
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