Page 374 of 521
373 Practical hints
What to do if …
Where will I find ...?
Unlocking/locking in an emergency
Opening/closing in an emergency
Resetting activated head restraints
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Bleeding the fuel system (Diesel engine only)
Batteries
Jump starting
Towing the vehicle
Fuses
Page 381 of 521

380 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
l
Only vehicles with Distronic*:
The red distance warning lamp
comes on while driving.
You are too close to the vehicle in front of you
to maintain selected speed.
Apply the brakes immediately to in-
crease the following distance.
Only vehicles with Distronic*:
The red distance warning lamp
comes on while driving and you
hear a warning chime sound.
You are gaining too rapidly on the vehicle
ahead of you.
The distance warning system has recog-
nized a stationary obstacle on your prob-
able line of travel.
Apply the brakes immediately.
Carefully observe the traffic situation.
You may need to brake or maneuver
to avoid hitting an obstacle.
W
The yellow fuel tank reserve
warning lamp comes on while
driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 315).
<
The red seat belt telltale comes
on after starting the engine with
all doors closed.
The seat belt telltale reminds you and your
passengers to fasten your seat belts before
driving off.
Fasten your seat belts.
The red seat belt telltale flashes
and you additionally hear an in-
termittent warning signal with
increasing intensity for a maxi-
mum of 60 seconds when the
vehicle’s speed exceeds
15 mph (25 km/h).
You and/or your front passenger have for-
gotten to fasten your seat belts.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Fasten your seat belts.
Remove the items from the front pas-
senger seat and put them in a safe
place.
Page 388 of 521
387 Practical hints
What to do if …
On the pages that follow, you will find a
compilation of the most important warning
and malfunction messages that may ap-
pear in the multifunction display.
For your convenience the messages are di-
vided into two sections:
Text messages (
page 388)
Symbol messages (
page 398)
iSwitching on the ignition causes all in-
strument cluster lamps (except low
beam headlamp indicator lamp, high
beam headlamp indicator lamp, and
turn signal indicator lamps unless acti-
vated) as well as the multifunction dis-
play to come on. Make sure the lamps
and multifunction display are in work-
ing order before starting your journey.
Page 451 of 521

450 Practical hintsBatteriesYour vehicle is equipped with two batter-
ies:
Main battery (battery for starter and
electrical consumers; located in the
trunk)
Auxiliary battery (back-up battery; sta-
bilizes the electrical system if the main
battery is discharged; located in the en-
gine compartment)
The main battery is in the trunk under the
luggage box. Remove the luggage box
(
page 423).
Vehicles with spare wheel1Negative terminal
2Positive terminalWarning!
G
Jump starting must only be done using the
main battery in the trunk.
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 326).
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.
Page 455 of 521

454 Practical hintsJump 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
converter
1 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 more powerful 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.
1Vehicles with gasoline engine only.
!Jump starting may only be performed
on the main battery installed in the
trunk.
Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If the engine does not run after several
unsuccessful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter
1.
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 attached to a battery.
Page 456 of 521
455 Practical hints
Jump starting
The battery is located in the trunk under-
neath the luggage box (
page 423). Only
jump start the vehicle from the battery in
the trunk.
Make sure the two vehicles do not
touch.
Turn off all electrical consumers.
Apply parking brake.
Shift gear selector lever to positionP.
Open the trunk.
Connect positive terminals1 and3
of the batteries with the jumper cable.
Clamp cable to charged battery3
first.
1Positive terminal of discharged battery
2Negative terminal of discharged bat-
tery
3Positive terminal of charged battery
4Negative terminal of charged 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 326).
!Never invert the terminal connections!
Page 457 of 521
456 Practical hintsJump starting
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.Now you can again turn on the electrical
consumers. Do not turn on the lights under
any circumstances.
Remove the jumper cables first from
negative terminals2 and4 and then
from positive terminals1 and3.
Now you can turn on the lights.
Have the battery checked at the near-
est authorized Mercedes-Benz Center.
iThe message
Malfunction - electric
consumers switched off
may appear
in the instrument cluster. It will disap-
pear as soon as the battery is suffi-
ciently charged.
!Do not tow-start the vehicle.
Page 460 of 521

459 Practical hints
Towing the vehicle
iTo signal turns while being towed with
the hazard warning flasher in use, turn
SmartKey in starter switch to
position2 and activate the combina-
tion switch for the left or right turn sig-
nal in the usual manner – only the
selected turn signal will operate.
Upon canceling the turn signal, the haz-
ard warning flasher will operate again.
!When towing the vehicle with all wheels
on the ground, please note the follow-
ing:
With the automatic central locking acti-
vated and the SmartKey in starter
switch position2, or KEYLESS-GO*
start/stop button in position2, the ve-
hicle doors lock if the left front wheel
as well as the right rear wheel are turn-
ing at vehicle speeds of approximately
9 mph (15 km/h) or more.
Switch off the tow-away alarm
(page 103).
To prevent the vehicle door locks from
locking, deactivate the automatic cen-
tral locking (
page 129).
Towing of the vehicle should only be
done using the properly installed tow-
ing eye bolt. Never attach tow cable,
tow rope or tow rod to the vehicle chas-
sis, frame or suspension parts.
iThe gear selector lever will remain
locked in positionP and the SmartKey
will not turn in the starter switch if the
battery is disconnected or discharged.
For more information see “Battery”
(page 450) or “Jump starting”
(page 454).
For information on manual unlocking of
the gear selector lever,
see (page 428).