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 336).
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.
W463.boo Seite 326 Montag, 19 . November 2007 8:41 08
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 91) 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.
W463.boo Seite 327 Montag, 19 . November 2007 8:41 08
Page 329 of 457
328 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
ú(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 impact 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 at an
authorized Merc edes-Benz Light
Truck Center as soon as possible .
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 malfunctions
through the readout of diagnostic
trouble codes. It is located near the
hood lock release on the upper left of
the footwell.
iSome states may by law require you to visit
a workshop as soon as the engine malfunction
indicator lamp comes on. Check local require-
ments.
W463.boo Seite 328 Montag, 19 . November 2007 8:41 08
Page 330 of 457
329
Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
ú(USA only)
±(Canada only)
The yellow engine malfunc-
tion indicator lamp comes on
while driving.A loss of pressure has been
detected in the fuel system. The fuel
filler cap may not be closed properly
or the fuel system may be leaky.Check the fuel filler cap (page 264).
If it is not closed properly:
Close the fuel filler cap.
If it is closed properly:
Have the fuel system checked at an
authorized Mercedes-Benz Light
Truck Center.
Your fuel tank is empty.After refueling start, turn off and
restart the engine th ree or four times
in succession.
The limp-home (emergency opera-
tion) mode is canceled. You do not
need to have your vehicle checked.
W463.boo Seite 329 Montag, 19 . November 2007 8:41 08
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 di fferential 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 336).
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 94).
Exceptions: (
page 93).
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 336).
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 Merc edes-Benz Light
Truck Center as soon as possible.
W463.boo Seite 330 Montag, 19 . November 2007 8:41 08
Page 333 of 457
332 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 co ntact 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.
W463.boo Seite 332 Montag, 19 . November 2007 8:41 08
Page 334 of 457
333
Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
HUSA only:
Combination low tire
pressure/TPMS malfunction
telltale
1 for the Advanced TPMS
illuminates continuously.
Canada only:
Low tire pressure telltale
1 for
the Advanced TPMS illuminates
continuously.
1Depending on vehicle production date.
The Advanced TPMS detects a loss of
pressure in at least one tire.Carefully bring the vehicle to a halt, avoiding
abrupt steering and br aking maneuvers. Ob-
serve the traffic situation around you.
Read and observe messages in the multifunc-
tion display (
page 336).
If the tire inflation pressure in the respective
tire(s) has (have) been corrected, the combina-
tion low tire pressure/TPMS malfunction telltale
goes out after few minutes driving.
USA only:
Combination low tire
pressure/TPMS malfunction
telltale
1 for the Advanced TPMS
flashes for 60 seconds and then
stays illuminated.
There is a malfunction in the Ad-
vanced TPMS.Read and observe messages in the multifunc-
tion display (
page 336).
Have the Advanced TPMS checked at an
authorized Mercedes-Benz Light Truck Cen-
ter.
After the malfunction has been remedied the
combination low tire pressure/TPMS malfunc-
tion telltale goes out af ter few minutes driving.
W463.boo Seite 333 Montag, 19 . November 2007 8:41 08
Page 336 of 457
335
Practical hints
What to do if …
Lamp in center console
ProblemPossible cause/consequenceSuggested solution
56The front passenger front air
bag off indicator lamp comes
on and remains illuminated.A BabySmartTM child seat is installed on
the front passenger seat. Therefore the
passenger front air bag is switched off.
The system is malfunctioning when there
is no BabySmartTM child seat installed on
the front passenger seat.
Have the system checked at an
authorized Mercedes-Benz Light
Truck Center as soon as possible.
The front passenger front air
bag off indicator lamp does not
come on or does not remain
illuminated with a
BabySmart
TM child seat
properly installed on the front
passenger seat.
The system is malfunctioning.Make sure there is nothing between
seat cushion and child seat and check
installation of the child seat.
If the front passenger front air bag off
indicator lamp remains out, have the
system checked at an authorized
Mercedes-Benz Light Truck Center as
soon as possible.
Do not use the BabySmart
TM restraint
to transport children on the front
passenger seat until the system has
been repaired.
W463.boo Seite 335 Montag, 19 . November 2007 8:41 08
