2011 MERCEDES-BENZ M-Class brake light

Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Enabled
See Operator's
ManualThe front-passenger air bag is enabled during the journey,
although:
R there is a child, a small adult or an object weighing less than the
system's weight threshold is on the front-passenger seat.
R the front-passenger seat is unoccupied
The system may detect the additional weight of objects on the
seat or forces acting on the seat.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XOpen the front-passenger door.XRemove the child and the child restraint system from the front-
passenger seat.XIf necessary, secure the child in a child restraint system on a
suitable rear seat.XMake sure that no forces are acting on the seat, such as:
R trapped books, bags, etc. lying on, behind or beside the seat
R head restraints pressing against the headliner
The system may otherwise detect these forces and interpret the
seat occupant's weight as greater than it actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 indicator lamps (Y page 42) and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
Display messages225On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 225Z

Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabled
See Operator's
ManualThe front-passenger air bag is disabled during the journey even
though an adult or a person larger than a certain size is occupying
the front-passenger seat. If additional forces are applied to the
seat, the weight the system detects may be too low.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XHave the occupant get out of the vehicle.XSet the seat higher ( Y page 94).XMake sure that no objects are exerting force on the seat, e.g.
books, bags, etc. lying under, behind or beside the seat. These
forces may otherwise cause the system to detect too low a
weight and interpret the seat occupant's weight as less than it
actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 (Y page 42) indicator lamps and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual cannot appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
XVisit a qualified specialist workshop immediately.GWarning
If the 42 indicator lamp remains lit with an adult occupant on the front-passenger
seat even after performing the above corrective steps, do not have any passenger use the front-
passenger seat until the system has been repaired.
Display messages227On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 227Z

BrakesDisplay messagesPossible causes/consequences and M SolutionsABS
ABS, ESP
Unavailable See
Operator's ManualGRisk of accident
ABS (Anti-lock Brake System) and ESP ®
(Electronic Stability
Program) and therefore also PRE-SAFE ®
are temporarily
unavailable. The self-diagnosis function might not be complete,
for example.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a short distance making slight steering
movements at a speed above 12 mph (20 km/h)
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
ABS, ESP ®
and therefore also PRE-SAFE ®
are not available due to
undervoltage. BAS has also been deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.ABS
ABS, ESP
Inoperative See
Operator's ManualGRisk of accident
ABS, ESP ®
and therefore also PRE-SAFE ®
are not available due to
a malfunction. BAS has also been deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.228Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M Solutions$
(USA only)
J
(Canada only)
EBV, ABS, ESP
Inoperative See
Operator's ManualGRisk of accident
EBD (Electronic Brake-force Distribution), ABS (Anti-lock Brake
System), ESP ®
(Electronic Stability Program) and therefore also
PRE-SAFE ®
are not available due to a malfunction. BAS (Brake
Assist) is also deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.#
Brake WearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.$
(USA only)
!
(Canada only)
Release Parking
BrakeYou are driving with the parking brake engaged. A warning tone
also sounds.XRelease the parking brake.$
(USA only)
J
(Canada only)
Check Brake Fluid
LevelGRisk of accident
There is insufficient brake fluid in the brake fluid reservoir. In
addition, the red warning lamp $(USA only) or J (Canada
only) in the instrument cluster lights up and a warning tone sounds.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not rectify the malfunction.GWarning
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
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 catching fire. You can be
seriously burned.
Display messages229On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 229Z

Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed.Display messagesPossible causes/consequences and M Solutionsb
Cornering Lamp Left
or
Cornering Lamp
RightThe left or right-hand cornering light is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Low Beam Left
or
Low Beam RightThe left or right-hand low-beam headlamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Trailer Tail Lamp
Left
or
Trailer Tail Lamp
RightThe left or right-hand trailer tail light is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Trailer Turn
Signal Left
or
Trailer Turn
Signal RightThe left or right-hand trailer turn signal lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Trailer Brake LampThe trailer brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Turn Signal Rear
Left
or
Turn Signal Rear
RightThe rear left-hand or rear right-hand turn signal is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.230Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsÆ
Reduce speed to
under 12 MPHGRisk of accident
You are exceeding the speed permissible for the selected off-road
level.
XAdjust your driving style to the altered handling characteristics.XOnly make slight steering movements and avoid fast steering
movements.XTake account of the altered handling characteristics.XDo not driver faster than 12 mph(20 km/h).8
Locking System
Inoperative
Service RequiredThe differential locks are faulty. XDo not drive faster than 50 mph (80 km/h).XHave the vehicle checked at a qualified specialist workshop.8
Diff. Lock System
Overheated - Wait
brieflyThe differential locks are too hot and have been disengaged.XDrive on carefully.XAllow the differential locks to cool down.
The differential locks reengage as soon as they have cooled
down.8
Stop vehicle,
engage parking
brakeA gearshift process has been canceled. LOW RANGE is in the
neutral position. There is no connection between the engine and
the drive wheels.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake. Do not continue driving under any
circumstances.XRepeat the gearshift process.Å
Service Required
If parked engage
pk. brakeThe LOW RANGE system is malfunctioning. XDo not drive faster than 50 mph (80 km/h).XEngage the parking brake to park.XHave the vehicle checked at a qualified specialist workshop.Å
Max. Speed 25 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.Å
Max. Speed 40 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.238Display messagesOn-board computer and displays
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Safety systemsProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running. GRisk of accident
ABS (Anti-lock Brake System) is deactivated due to a malfunction.
Therefore, BAS (Brake Assist), ESP ®
(Electronic Stability Program),
EBD (Electronic Brake-force Distribution) and PRE-SAFE ®
are also
deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available.
!
The yellow ABS warning
lamp is lit while the
engine is running.GRisk of accident
The on-board voltage is too low. ABS has been deactivated due to
undervoltage.
Therefore, ESP ®
, BAS and PRE-SAFE ®
are also deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XSwitch off consumers that are not required, e.g. the rear window
defroster or interior lighting.
ABS will be available again as soon as the vehicle's on-board
electrical system voltage increases.
If the warning lamp is still on:
XHave the battery and alternator checked at a qualified specialist
workshop.!
The yellow ABS warning
lamp is lit while the
engine is running.Self diagnosis is not yet complete.XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).Warning and indicator lamps in the instrument cluster249On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 249Z

Driving systemsProblemPossible causes/consequences and M Solutions·
The red DTR distance
warning lamp lights up
while the vehicle is in
motion. A warning tone
also sounds.GRisk of accident
A warning is issued if:
R you are approaching a vehicle in front at too great a speed
R DISTRONIC has detected a stationary obstacle in your line of
travel
XBe prepared to brake immediately.XPay careful attention to the traffic situation. You may have to
brake or take evasive action.
Tires
ProblemPossible causes/consequences and M Solutionsh
USA only:
The yellow combination
low tire pressure
telltale/TPMS
malfunction telltale for
the TPMS is on.GRisk of accident
The TPMS has detected a loss of pressure in at least one of the
tires.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XObserve the additional display messages in the multifunction
display.XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 331).XIf necessary, change a wheel ( Y page 340).h
USA only:
The yellow combination
low tire pressure
telltale/TPMS
malfunction telltale for
the TPMS flashes for 60
seconds and then
remains illuminated.The TPMS is faulty.XObserve the additional display messages in the multifunction
display.XVisit a qualified specialist workshop.GWarning
Each tire, including the spare (if provided), should be checked every other week when cold and
inflated to the inflation pressure recommended 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
Warning and indicator lamps in the instrument cluster253On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 253Z