Page 406 of 561

405 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 56).
The ESP
® control unit may be
malfunctioning.
The driving safety systems
may not be available.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the
multifunction display (
page 416).
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 and notify an autho-
rized Mercedes-Benz Light Truck Cen-
ter. 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 414 of 561

413 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
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should determine the proper tire infla-
tion pressure for those tires).
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat 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 TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er’s responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined 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 subse-
quent vehicle start-ups as long as the mal-
function exists. When the malfunction
indicator is illuminated, the system may not
be able to detect or signal low tire pressure
as intended.
TPMS malfunctions may occur for a variety
of reasons, including the installation of in-
compatible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after replacing
one or more tires or wheels on your vehicle
to ensure that the replacement or alternate
tires and wheels allow the TPMS to continue
to function properly.
Page 417 of 561

416 Practical hintsWhat to do if …Vehicle status messages in the multifunction display
Warning and malfunction messages
appear in the multifunction display located
in the instrument cluster.
Certain warning and malfunction messag-
es are accompanied by an audible signal.
Address these messages accordingly and
follow the additional instructions given in
this Operator’s Manual.
Selecting the vehicle status message
memory menu in the control system
(page 173) displays both cleared and
uncleared messages.
High-priority messages appear in the
multifunction display in red color.Certain messages of high priority cannot
be cleared from the multifunction display
using the reset button (
page 158) or
buttonj,k,ÿ, orè on the
multifunction steering wheel.
Other messages of high priority and mes-
sages of less immediate priority can be
cleared from the multifunction display
using the reset button (page 158) or
buttonj,k,ÿ, orè on the
multifunction steering wheel. They are
then stored in the vehicle status message
memory (
page 173). Remember that
clearing a message will only make the mes-
sage disappear. Clearing a message will
not correct the condition that caused the
message to appear.
Warning!
G
All categories of messages contain
important information which should be
taken note of and, where a malfunction is
indicated, addressed as soon as possible at
an authorized Mercedes-Benz Light Truck
Center.
Failure to repair condition noted may cause
damage not covered by the Mercedes-Benz
Limited Warranty, or result in property dam-
age or personal injury.Warning!
G
No messages will be displayed if either the
instrument cluster or the multifunction
display is inoperative.
Contact the nearest authorized
Mercedes-Benz Light Truck Center.
Page 419 of 561
418 Practical hintsWhat to do if …Text messagesDisplay message
Possible cause/consequence
Possible solution
ABS
Malfunction
Visit workshop
The ABS has detected a malfunction
and has switched off.
The ESP
® and the BAS are also deac-
tivated.
The brake system is still functioning
normally but without the ABS avail-
able.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
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.
Display malfunction
Visit workshop
The ABS or the ABS display is mal-
functioning.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability
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.
Page 421 of 561

420 Practical hintsWhat to do if …Display message
Possible cause/consequence
Possible solution
ESP
unavailable
See Operator’s Manual
If the yellow ESP
® warning
lampv flashes while driving and
this message appears, the electron-
ic traction system has switched off
to prevent overheating of the drive
wheel brakes.
As soon as the brakes have cooled off, the
electronic traction system switches on again.
The message in the multifunction display disap-
pears and the ESP
® warning lampv goes
out.
The self-diagnosis has not yet been
completed yet.
The display will clear after driving a short
distance at a vehicle speed of above
12 mph (20 km/h).
Malfunction
Visit workshop
In addition, the yellow ESP
® warning
lampv comes on.
The ESP
® has detected a malfunc-
tion and switched off.
The ABS may still be operational.
Continue driving with added caution.
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.
Display malfunction
Visit workshop
In addition, the yellow ESP
® warning
lampv comes on.
The ESP
® or the ESP
® display is
malfunctioning.
Continue driving with added caution.
Visit an authorized Mercedes-Benz Light
Truck Center as soon as possible.
Failure to follow these instructions increases
the risk of an accident.
Page 428 of 561

427 Practical hints
What to do if …
Display message
Possible cause/consequence
Possible solution
Check tires
Then reactivate
Run Flat Indicator
There was a warning message about
a loss in the tire inflation pressure
and the Run Flat Indicator has not
been reactivated yet.
Make sure that the correct tire inflation pressure is set
for each tire.
Then reactivate the Run Flat Indicator.
Run Flat Indicator
inactive
Run Flat Indicator is malfunctioning.
Have the Run Flat Indicator checked by an authorized
Mercedes-Benz Light Truck Center.
Run Flat Indicator
unavailable
The Run Flat Indicator has been
switched off due to an error.
Have the Run Flat Indicator checked by an authorized
Mercedes-Benz Light Truck Center.
Tire pressure
Check tires
The Run Flat Indicator indicates that
the pressure is too low in one or more
tires.
Carefully bring the vehicle to a halt, avoiding abrupt
steering and braking maneuvers. Observe the traffic sit-
uation around you.
Check and adjust tire inflation pressure as required
(page 365).
If necessary, change the wheel (
page 478).
Reactivate the Run Flat Indicator after adjusting the tire
inflation pressure values (
page 365).
Page 429 of 561

428 Practical hintsWhat to do if …Display message
Possible cause/consequence
Possible solution
Tire pressure displayed
only after driving
a few minutes
Vehicles with Advanced TPMS*:
The tire inflation pressure is being checked.
Drive the vehicle for a few minutes.
Tire pressure monitor
inoperative
The TPMS or Advanced TPMS* is
malfunctioning.
Have the TPMS or Advanced TPMS* checked by an
authorized Mercedes-Benz Light Truck Center.
Tire pressure monitor
inoperative
No wheel sensors
There are wheels without wheel sensors
mounted (e.g. winter tires).
Have the TPMS or Advanced TPMS* checked by an
authorized Mercedes-Benz Light Truck Center.
Have the wheel sensors installed by an authorized
Mercedes-Benz Light Truck Center.
Tire pressure monitor
temporarily
unavailable
The TPMS or Advanced TPMS* is unable to
monitor the tire pressure due to
a nearby radio interference source
excessive wheel sensor temperatures
As soon as the causes for the malfunction are no
longer present, the TPMS or Advanced TPMS* auto-
matically becomes active again after a few minutes
of driving.
Tire pressure monitor
Wheel sensor missing
One or more sensors malfunction (e.g. bat-
tery in one or more wheel sensor is empty).
One or more wheels without wheel sensors
mounted (e.g. spare tire).
Have the TPMS or Advanced TPMS* checked by an
authorized Mercedes-Benz Light Truck Center.
Have the wheel sensors installed by an authorized
Mercedes-Benz Light Truck Center.
Vehicles with Advanced TPMS*:
The tire pressure for the respective tire is shown in
the multifunction display.
Page 432 of 561
431 Practical hints
What to do if …
Display symbol
Display message
Possible cause/consequence
Possible solution
;
(USA only)
!
(Canada only)
Release
parking brake
You are driving with the parking
brake set.
Release the parking brake (
page 56).
;
(USA only)
3
(Canada only)
Changed braking behavior
Drive with extreme care
A malfunction in the Electronic
Brake Proportioning
(page 102) was detected.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the multi-
function display.
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 an accident.