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 377 of 521

376 Practical hintsWhat to do if …Problem
Possible cause/conse-
quence
Suggested solution
;
(USA only)
3
(Canada only)
The red brake warning lamp
comes on while driving and
you hear a warning sound.
You are driving with the park-
ing brake set.
Release the parking brake.
Observe the additional message in
the multifunction display.
The red brake warning lamp
comes on while driving.
There is a malfunction in
the electrohydraulic brake
system.
There is insufficient brake
fluid in the reservoir.
Risk of accident! Do not drive any fur-
ther. Consult a Mercedes-Benz
Service Center. Under no circum-
stances should you top up the brake
fluid. This will not solve the problem.
Warning!
G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. Do not add
brake fluid before checking the brake
system.
Overfilling the brake fluid reservoir can re-
sult in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.
Page 378 of 521

377 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
ú
(USA only)
±
(Canada only)
The yellow engine mal-
function indicator lamp
comes on while driving.
There is a malfunction in:
The fuel management system
The ignition system (Gasoline engine)
The emission control system
Systems which affect emissions
Such malfunctions may result in excessive
emissions values and may switch the engine
to its limp-home (emergency operation)
mode.
Have the vehicle checked as soon as possi-
ble by an authorized Mercedes-Benz Center.
An on-board diagnostic connector is used
by the service station to link the vehicle to
the shop diagnostics system. It allows the
accurate identification of system malfunc-
tions through the readout of diagnostic trou-
ble codes. It is located in the front left area
of the footwell next to the parking brake.
A loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.
Check the fuel cap.
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an autho-
rized Mercedes-Benz Center.
Page 379 of 521
378 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
ú
(USA only)
±
(Canada only)
The yellow engine malfunction
indicator lamp comes on while
driving.
Your fuel tank is empty.
After refuelling start, turn off and re-
start the engine three or four times in
succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
Diesel engine: The fuel tank is empty. The en-
gine is running in emergency operation
mode.
Bleed the fuel system (
page 449).
The limp-home mode is canceled. You do
not need to have your vehicle checked.
Diesel engine: The diesel engine electronics
are malfunctioning.
Full engine performance is not available.
Have the fuel system checked by an au-
thorized Mercedes-Benz Center.
Page 380 of 521

379 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
D
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently,
there is a leak in the cooling system.
If the coolant level is correct, the electric ra-
diator fan may be broken.
Immediately add coolant to prevent
engine from overheating
(page 325).
Have the cooling system checked.
If the coolant temperature is below
257°F (125°C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257°F (125°C).
Stop as soon as possible in a safe lo-
cation and allow the engine and cool-
ant to cool down.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
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 391 of 521

390 Practical hintsWhat to do if …Display
Display message
Possible cause/consequence
Possible solution
Distronic
Currently unavailable
See Operator’s Manual
Distronic* is switched off if:
the Distronic* cover in the area
of the radiator grille is dirty
the functionality is impaired by
heavy rain or thick fog
If necessary, clean the Distronic* cover in the area of
the radiator grille.
Restart the vehicle.
or
Distronic* becomes operational again without the engine
being restarted when:
dirt on the grille falls off while driving (e.g. slush or
snow)
the system recognizes full sensor availability (due to
lessening rain or the road surface drying)
the message in the multifunction display disappears
the speed last stored flashes in the multifunction dis-
play for 5 seconds.
You can operate Distronic* as usual again.
Warning!
G
Distronic cannot take weather conditions
into account. Switch off Distronic* or do not
turn it on if the sensor is dirty or visibility is
diminished as a result of snow, rain or fog.
The distance control may be impaired even
before the system is able to detect a dirty
sensor. The message
Distronic
Currently unavailable
See Operator’s Manualwill be displayed in the multifunction display
and Distronic* will be turned off.
Page 393 of 521
392 Practical hintsWhat to do if …Display
Display message
Possible cause/consequence
Possible solution
ESP
Display malfunction
Visit workshop
The ESP
® or the ESP
® display is
malfunctioning.
Continue driving with added caution.
Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
Failure to follow these instructions increases
the risk of an accident.
P
Gear selector lever
in Park
You have attempted to turn off the
engine with the KEYLESS-GO*
start/stop button with the gear se-
lector lever not inP. You have
opened the driver’s door with the
gear selector lever not inP.
Place the gear selector lever in positionP.
P/N
Shift to
Neutral or Park
You have attempted to start the en-
gine with the KEYLESS-GO*
start/stop button while the gear se-
lector lever was in positionR orD.
Place the gear selector lever in positionP
orN. Make sure the brake pedal is de-
pressed.