Page 414 of 585
413 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)
Battery
Jump starting
Towing the vehicle
Fuses
Page 415 of 585

414 Practical hintsWhat to do if …Lamps in instrument clusterGeneral information:
If any of the following lamps in the instru-
ment cluster fails to come on during thebulb self-check when switching on the
ignition, have the respective bulb checked
and replaced if necessary.Problem
Possible cause/consequence
Suggested solution
-
The yellow ABS indicator lamp
comes on while the engine is
running.
ABS has detected a malfunction and has
switched off. The BAS, ESP
®, EBP and 4-ETS
are also switched off (see messages in multi-
function display).
The brake system is still functioning normally
but without the ABS available.
If the ABS control unit is malfunctioning,
other systems such as the navigation
system* or the automatic transmission may
also be malfunctioning.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the
multifunction display (
page 428).
Have the system checked at an
authorized Mercedes-Benz Light
Truck Center as soon as possible.
Failure to follow these instructions
increases the risk of an accident.
The charging voltage has fallen below
10 volts. The ABS has switched off.
The battery might not be charged sufficiently.
When the voltage is above this value
again, the ABS is operational again and
the ABS indicator lamp should go out.
If the ABS indicator lamp should go out:
Have the generator (alternator) and
the battery checked.
Page 416 of 585

415 Practical hints
What 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
parking brake set.
Release the parking brake
(page 57).
There is insufficient brake fluid
in the reservoir.
Risk of accident! Carefully stop the
vehicle in a safe location or as soon it
is safe to do so.
Apply the parking brake (
page 65).
Notify an authorized Mercedes-Benz
Light Truck Center. Do not add 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 res-
ervoir can result 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 418 of 585

417 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
?
(USA only)
±
(Canada only)
The yellow engine malfunc-
tion indicator lamp comes on
while driving.
There is a malfunction in:
The fuel management system
The ignition system
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 opera-
tion) mode (
page 198).
Have the vehicle checked as soon as
possible by an authorized
Mercedes-Benz Light Truck 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 identi-
fication of system malfunctions
through the readout of diagnostic
trouble codes. It is located in the
front left area of the footwell next to
the parking brake pedal.
i
Some states may by law require you to visit
a workshop immediately as soon as the engine
malfunction indicator lamp comes on. Check
local requirements.
Page 419 of 585
418 Practical hintsWhat to do if …Problem
Possible cause/conse-
quence
Suggested solution
?
(USA only)
±
(Canada only)
The yellow engine malfunction
indicator lamp comes on while
driving.
A loss of pressure has been
detected in the fuel system.
The fuel cap may not be closed
properly.
The fuel system may be leaky.
Check the fuel cap (
page 352).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an
authorized Mercedes-Benz Light Truck
Center.
Your fuel tank is empty.
After refueling start, turn off and
restart the engine three or four times in
succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
Page 422 of 585
421 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
<
The red seat belt telltale comes
on for a maximum of 6 seconds
after starting the engine.
The seat belt telltale reminds you and your
passengers to fasten your seat belts before
driving off.
Fasten your seat belts.
Regardless of whether the seat belts
are fastened or not, the seat belt tell-
tale always comes on and remains lit
for 6 seconds after starting the
engine.
<
You hear a warning chime for a
maximum of 6 seconds after
starting the engine.
You have forgotten to fasten your seat belt.
Fasten your seat belts.
The warning chime stops sounding.
Page 423 of 585

422 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
<
The red seat belt telltale comes
on while the vehicle is standing
still and the engine is running or
during driving.
You and/or your front passenger have
forgotten to fasten your seat belts.
Fasten your seat belts.
The seat belt telltale goes out.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out.
<
During driving the red seat belt
telltale flashes and you addition-
ally hear an intermittent warning
chime with increasing intensity.
The vehicle’s speed once exceeded 15 mph
(25 km/h) and you and/or your front pas-
senger have forgotten to fasten your seat
belts.
Fasten your seat belts.
The seat belt telltale goes out and the
warning chime stops sounding.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out and the
warning chime stops sounding.
i
After 60 seconds with an unfastened seat
belt the warning chime stops sounding and the
seat belt telltale illuminates continuously. The seat belt telltale will only go out if both, the
driver’s and front passenger’s seat belt are
fastened, or the vehicle is standing still and a
front door is opened.
Page 435 of 585
434 Practical hintsWhat to do if …Display message
Possible cause/consequence
Possible solution
DISTRONIC
currently unavailable
See Operator’s Manual
Distronic* is deactivated because
the Distronic* cover in the
radiator grille is dirty
the functionality is impaired by
heavy precipitation or fog
Clean the Distronic* cover in the radiator
grille (
page 408).
Restart the vehicle.
Distronic* becomes operational again without
the engine being restarted when
dirt on the radiator grille has fallen off while
driving (e.g. slush or snow)
the system recognizes full sensor
availability due to lessening rain or because
the road is drying, for example
the message in the multifunction display
disappears
You can then operate Distronic* as usual again.