386 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause/consequence
Possible solution
.
Right mirror
turn signal
The turn signal in the right exterior rear
view mirror is malfunctioning. This mes-
sage will only appear if a critical number of
LEDs have stopped working.
Contact an authorized Mercedes-Benz
Center as soon as possible.
L
Tele Aid
inoperative
One or more main functions of the
Tele Aid system are malfunctioning.
Have the Tele Aid system checked by
an authorized Mercedes-Benz Center.
Tele Aid
battery
The emergency power battery for the
Tele Aid system is malfunctioning. If the
vehicle battery is also dead, Tele Aid will
not be operational.
Have the Tele Aid system checked by
an authorized Mercedes-Benz Center.
1
Restraint system
malfunction
Visit workshop
The system is malfunctioning.
Drive with added caution to the near-
est authorized Mercedes-Benz Center.
Warning!
G
In the event a malfunction of the SRS is indi-
cated as outlined above, the SRS may not be
operational.
For your safety, we strongly recommend
that you contact an authorized
Mercedes-Benz Center immediately
to have the system checked; otherwise the
SRS may not be activated when needed in
an accident, which could result in serious or
fatal injury, or it might deploy unexpectedly
and unnecessarily which could also result in
injury.
402 Practical hintsReplacing SmartKey batteriesIf the batteries in the SmartKey/SmartKey
with KEYLESS-GO* are discharged, the ve-
hicle can no longer be locked or unlocked.
It is recommended to have the batteries re-
placed at an authorized Mercedes-Benz
Center.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.SmartKey/SmartKey with
KEYLESS-GO*
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key out of the
SmartKey/SmartKey with
KEYLESS-GO* (
page 396).
1Mechanical key
2Battery compartment
Insert mechanical key 1 into opening.
Press mechanical key 1 in direction of
arrow.
The battery compartment is unlatched.
Warning!
G
Batteries contain poisonous and corrosive
substances. Therefore keep the batteries
out of reach of children.
If a battery is swallowed, seek medical help
immediately.
i
When inserting the batteries, make sure
they are clean and free of lint.
i
When changing batteries, always replace
both batteries.
The required replacement batteries are available
at any authorized Mercedes-Benz Center.
403 Practical hints
Replacing SmartKey batteries
Pull battery compartment 2 out of the
housing.
3Batteries
4Contact springs
Pull out batteries3.
Using a line-free cloth, insert new bat-
teries 3 under contact springs 4 with
the positive terminal (+) side facing up.
Return battery compartment 2
(page 402) into housing until it locks
into place.
Slide the mechanical key back into the
SmartKey/SmartKey with
KEYLESS-GO*.
Check the operation of the SmartKey/
SmartKey with KEYLESS-GO*.
420 Practical hintsBatteryThe battery is located on the right hand
side of the trunk under the luggage box
(page 395).
1Positive terminal cover
2Negative terminalWarning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
Warning!
G
Failure to follow these instructions can
result in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 291).
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.
!
Depending on vehicle production date, the
battery is a Valve-Regulated Lead Acid (VRLA)
battery, also referred to as “fleece” battery.
Such batteries do not require topping-up of the
electrolyte level. VRLA batteries therefore do not
have cell caps and the battery cover is non-re-
movable. Do not attempt to open the battery as
otherwise the battery will be damaged.
Even though VRLA batteries do not require top-
ping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the bat-
tery condition must be checked periodically by
performing a battery conductance test. Refer to
Maintenance Booklet for battery condition test-
ing intervals.
The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the facto-
ry-equipped battery.
421 Practical hints
Battery
Disconnecting the battery
Depress parking brake firmly or move
gear selector lever to positionP.
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Vehicles with KEYLESS-GO*:
Press the start/stop button until
the engine shuts off.
Open the driver’s door.
Open the trunk.
Read and observe safety instructions
and precautions (
page 420).
Remove the luggage box (
page 395).
Disconnect battery negative lead2.
Remove cover1 from the positive ter-
minal.
Disconnect the battery positive lead.
Removing the battery
Remove the screw-nuts securing the
battery.
Remove the battery bracket.
Pull out the battery ventilation tube
from the battery (depending on battery
arrangement in your vehicle model, the
battery ventilation tube is located on
the left or right side of the battery).
Take out the battery.
!
As with any other battery, disconnect the
battery if you do not intend to operate your vehi-
cle for an extended period of time to prevent bat-
tery discharge or connect an accessory battery
charge unit expressly approved by
Mercedes-Benz for your vehicle model to main-
tain the battery charge. Contact an authorized
Mercedes-Benz Center for further information.
The battery, the battery ventilation hose and the
lateral plug must always be securely installed
when the vehicle is in operation.
!
Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact your authorized
Mercedes-Benz Center for further information.
Warning!
G
With a disconnected battery
you will no longer be able to turn the
SmartKey in the starter switch and
pressing the KEYLESS-GO* start/stop
button on the gear selector lever will
have no effect
the gear selector lever will remain
locked in positionP
422 Practical hintsBatteryCharging and reinstalling the battery
Charge battery in accordance with the
instructions of the battery charger
manufacturer.
Reinstall the charged battery. Follow
the previously described steps in re-
verse order.
Reconnecting the battery
Turn off all electrical consumers.
Remove the SmartKey from the starter
switch.
Connect the positive lead and fasten its
cover.
Connect the negative lead.
Install the luggage box (
page 395).Batteries contain materials that can harm
the environment if disposed of improperly.
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.
Warning!
G
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 charg-
ing 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, permitting the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for infor-
mation and availability. Charge battery in
accordance with the separate instructions
for the accessory battery charger*.
!
The battery, its filler caps and the battery
ventilation tube must always be securely in-
stalled when the vehicle is in operation.
!
Never invert the terminal connections!
i
The following procedures must be carried
out following any interruption of battery power
(e.g. due to reconnection):
Set the clock (
page 159) (see COMAND
operator’s manual).
Resynchronize the side windows
(page 209).
Resynchronize the tilt/sliding sunroof
(page 214).
423 Practical hints
Jump starting
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:
Jump starting should only be performed
when the engine and catalytic convert-
er are cold.
Do not start the engine if the battery is
frozen. Let the battery thaw out first.
Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a higher voltage battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.
Use only jumper cables with sufficient
cross-section and insulated terminal
clamps.
Always make sure the jumper cables
are not on or near pulleys, fans or other
parts that move when the engine is
started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, 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 very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
!
Do not tow-start the vehicle.
!
Avoid repeated and lengthy starting
attempts.
Do not attempt to start the engine using a bat-
tery quick charge unit.
If the engine does not run after several unsuc-
cessful starting attempts, have it checked at the
nearest authorized Mercedes-Benz Center.
Excessive unburned fuel generated by repeated
failed starting attempts may damage the catalyt-
ic converter and may present a fire risk.
Make sure the jumper cables do not have loose
or missing insulation.
Make sure the cable clamps do not touch any
other metal part while the other end is still at-
tached to a battery.
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 291).
424 Practical hintsJump startingThe main battery is located in the trunk un-
derneath the luggage box (
page 395).
Only jump start the vehicle from the bat-
tery in the trunk.
Make sure the two vehicles do not
touch.
Turn off all electrical consumers.
Apply parking brake (
page 59).
Make sure the gear selector lever is set
to positionP.
Open the trunk.1Positive terminal of discharged battery
2Negative terminal of discharged bat-
tery
3Positive terminal of charged battery
4Negative terminal of charged battery
Connect positive terminals1 and3
of the batteries with the jumper cable.
Clamp cable to charged battery3
first.
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminals4 and2
of the batteries with the jumper cable.
Clamp cable to charged battery4
first.
Start the engine of the disabled vehi-
cle.
You can now turn on the electrical con-
sumers. Do not switch on the headlamps
under any circumstances.
Remove the jumper cables first from
negative terminals2 and4 and then
from positive terminals1 and3.
You can now switch on the headlamps.
Have the battery checked at the near-
est authorized Mercedes-Benz Center.
!
Never invert the terminal connections!