Page 327 of 457

326 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
;(USA only)
3(Canada only)
The red brake warning lamp
comes on while driving.There is insufficient brake fluid in the
reservoir.Risk of accident!
Carefully stop the vehicle in a safe
location or as soon as it is safe to do
so.
Apply the parking brake (page 62).
Do not drive any further.
Contact an authorized
Mercedes-Benz Light Truck Center.
Do not add brake fluid! This will not solve
the problem.
Read and observe messages in the
multifunction display (
page 338).
Warning!G
Driving with the brake warning lamp
illuminated 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 result in spilling brake fluid on
hot engine parts and the brake fluid catch-
ing fire. You could 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 328 of 457
327 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
;(USA only)
3(Canada only)
The red brake warning lamp
comes on while driving and
an acoustic warning sounds.You are driving with the parking
brake set.Release the parking brake
(
page 55).
;(USA only)
3(Canada only)
-
The red brake warning lamp
and the yellow ABS indicator
lamp come on when the
engine is running and an
acoustic warning sounds for
approximately 5 seconds.The EBB (page 92) has detected a
malfunction and has switched off.Continue driving with added caution.
Have the system checked at an autho-
rized Mercedes-Benz Light Truck
Center as soon as possible.
Failure to follow these instructions
increases the risk of accidents.
Warning!G
Driving with the brake warning lamp
illuminated can result in an accident. Have
your brake system checked immediately if
the brake warning lamp stays on.
Page 331 of 457

330 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
vThe yellow ESP® warning lamp
comes on and remains on while
driving.You have engaged the differential locks. The
ABS, ESP®, BAS, EBB and 4-ETS are switched
off.
The driving systems will switch on
again after the differential locks have
been disengaged.
Read and observe messages in the
multifunction display (
page 338).
The ESP® has been switched off with the
ESP® switch or has switched off due to a
malfunction.
Risk of accident!
When the ESP
® is switched off, it will not
stabilize the vehicle if the system recognizes
that the vehicle starts to skid or that a wheel
is spinning.
The cruise control is deactivated and cannot
be switched on.
Switch the ESP® back on (page 95).
Exceptions: (
page 94).
If leaving the ESP® switched off, adapt
your speed and driving to the prevail-
ing road and weather conditions.
If the ESP
® cannot be switched on:
Read and observe messages in the
multifunction display (
page 338).
Continue driving with added caution.
Adapt your speed and driving to the
prevailing road and weather condi-
tions.
Have the system checked at an
authorized Mercedes-Benz Light
Truck Center as soon as possible.
Page 332 of 457

331 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
vThe yellow ESP® warning lamp
comes on and remains on while
driving.The ESP® is deactivated because of inter-
rupted power supply. The ABS may still be
operational.Read and observe messages in the
multifunction display (
page 338).
The ESP®, ABS, BAS, EBB or 4-ETS has
detected a malfunction. All driving systems
are switched off.
Risk of accident!
Adapt your speed and driving to the
prevailing road conditions.Read and observe messages in the
multifunction display (
page 338).
The yellow fuel tank reserve warning lamp
comes on while driving.The fuel level has dropped below the reserve
mark.Refuel at the next gas station
(
page 264).
Read and observe messages in the
multifunction display (
page 338).
The yellow fuel tank reserve warning lamp is
blinking.The fuel cap is not closed tight.Check the fuel filler cap (page 264).
Read and observe messages in the
multifunction display (
page 338).
Page 333 of 457

332 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
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
telltale 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 belt.
The warning chime stops sounding.
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
passenger seat and put them in a safe
place.
The seat belt telltale goes out.
Page 334 of 457

333 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
telltale flashes and you
additionally 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
passenger seat and put them in a safe
place.
The seat belt telltale goes out and the
warning chime stops sounding.
iAfter 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 the front passenger’s seat belt are
fastened, or the vehicle is standing still and a
front door is opened.
Page 335 of 457
334 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
1The red SRS indicator lamp
comes on while driving.There is a malfunction in the restraint
systems. The air bags or Emergency
Tensioning Devices (ETDs) might deploy
unexpectedly or may not deploy in an
accident.Drive with added caution to the nearest
authorized Mercedes-Benz Light Truck
Center and have the system checked.
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 Light Truck Center
immediately to have the system checked;
otherwise the SRS may not deploy 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 an accident and/or
injury to you or to others.
Page 337 of 457

336 Practical hints
What to do if …
Warning!G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
Tire and Loading Information placard on the
driver’s door B-pillar or, if available, the tire
inflation pressure label on the inside of the
fuel filler flap. If your vehicle has tires of a
different size than the size indicated on the
Tire and Loading Information placard or the
tire inflation pressure label, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a Advanced Tire Pres-
sure Monitoring System (Advanced TPMS)
that illuminates a low tire pressure telltale
when one or more of your tires is signifi-
cantly underinflated. Accordingly, when the
low tire pressure telltale illuminates, you
should stop and check your tires as soon as
possible, and inflate them to the proper
pressure.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability. Please
note that the Advanced TPMS is not a sub-
stitute for proper tire maintenance, and it is
the driver’s responsibility to maintain cor-
rect tire pressure, even if underinflation has
not reached the level to trigger illumination
of the Advanced TPMS low tire pressure tell-
tale.
USA only: Your vehicle has also been
equipped with a Advanced TPMS malfunc-
tion indicator to indicate when the system is
not operating properly. The Advanced TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the telltale will flash
for approximately 1 minute and then remain
continuously illuminated. This sequence will
continue upon subsequent vehicle start-ups
as long as the malfunction exists.When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended.
Advanced TPMS malfunctions may occur for
a variety of reasons, including the installa-
tion of replacement or alternate tires or
wheels on the vehicle that prevent the Ad-
vanced TPMS from functioning properly. Al-
ways check the Advanced TPMS
malfunction telltale after replacing one or
more tires or wheels on your vehicle to en-
sure that the replacement or alternate tires
and wheels allow the Advanced TPMS to
continue to function properly.