trailer MERCEDES-BENZ GLK SUV 2012 Service Manual

Safety systems (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M
MSolutions !÷
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual ABS (Anti-lock Braking System), ESP
®
(Electronic Stability Pro-
gram), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function, hill
start assist and ESP ®
trailer stabilisation are temporarily unavail-
able.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. ÷
inoperative See inoperative See
Owner's Manual Owner's Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are unavailable due to a malfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷andå warning lamps light up in the
instrument cluster.
The self-diagnosis function may not be complete, for example.
ATTENTION ASSIST is deactivated.
G WARNING 252
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP
®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. T!
÷
inoperative See inoperative See
Owner's Manual Owner's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer stabi-
lisation are unavailable due to a malfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! warning lamps light up in
the instrument cluster and a warning tone sounds.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. J
Release parking Release parking
brake brake You are driving with the parking brake applied. A warning tone also
sounds.
X
Release the parking brake. Display
messages
253On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions 6
Rear centre mal‐ Rear centre mal‐
function Consult function Consult
workshop workshop G
WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
SRS has malfunctioned at the rear centre. The 6warning lamp
also lights up in the instrument cluster.
X Visit a qualified specialist workshop. 6
Left Left
windowbag
windowbag mal‐
mal‐
function Consult
function Consult
workshop workshop orRight
Right
windowbag malfunc‐
windowbag malfunc‐
tion Consult work‐ tion Consult work‐
shop shop There is a malfunction in the left-hand and/or right-hand window-
bag.
The
6 warning lamp also lights up in the instrument cluster.
G WARNING
The left or right windowbag may either be triggered unintentionally
or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Visit a qualified specialist workshop. Lights (4-button multifunction steering wheel)
i Display messages about LEDs:
This display message will only appear if all LEDs have failed. Display messages Possible causes/consequences and
M MSolutions b
Left cornering Left cornering
light light
orRight cor‐
Right cor‐
nering light
nering light The left or right-hand cornering light is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Left dipped beam Left dipped beam
or
Right dipped Right dipped
beam
beam The left or right-hand dipped-beam headlamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Trailer left tail Trailer left tail
lamp lamp
orTrailer
Trailer
right tail lamp
right tail lamp The left or right-hand trailer tail lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. Display
messages
257On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions b
Trailer left Trailer left
indic. indic.
orTrailer
Trailer
right indic
right indic The left or right-hand trailer turn signal lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. b
Trailer brake lamp Trailer brake lamp The trailer brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. b
Rear left indica‐ Rear left indica‐
tor tor
orRear right
Rear right
indicator
indicator The rear left-hand or rear right-hand turn signal is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Front left indica‐ Front left indica‐
tor tor
orFront right
Front right
indicator
indicator The front left-hand or front right-hand turn signal is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Left Left
mirror
mirror indica‐
indica‐
tor
tor orRight mir‐
Right mir‐
ror indicator
ror indicator The turn signal in the left-hand or right-hand exterior mirror is
faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Third brake lamp Third brake lamp The third brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Tail/brake lamp, Tail/brake lamp,
left left
orTail/brake
Tail/brake
lamp, right
lamp, right The left or right-hand tail lamp/brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. 258
Display
messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions b
malfunction malfunction The exterior lighting is faulty.
X
Visit a qualified specialist workshop. Vehicles with trailer tow hitch: a fuse may have blown.
X Check the fuses (Y page 346).
X If necessary, replace the blown fuse. Observe the warning notes
as you do so.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. b
AUTO AUTO
lights
lights inoper‐
inoper‐
ative
ative The light sensor is faulty.
X
Visit a qualified specialist workshop. b
Switch off lights Switch off lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã.Lights (12-button multifunction steering wheel)
i Display messages about LEDs:
This display message will only appear if all LEDs have failed. Display messages Possible causes/consequences and
M MSolutions b
Left cornering Left cornering
light light
orRight cor‐
Right cor‐
nering light
nering light The left or right-hand cornering light is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Left dipped beam Left dipped beam
or
Right dipped Right dipped
beam
beam The left or right-hand dipped-beam headlamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Trailer left tail Trailer left tail
lamp lamp
orTrailer
Trailer
right tail lamp right tail lamp The left or right-hand trailer tail lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. 260
Display
messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions b
Trailer left indi‐ Trailer left indi‐
cator cator
orTrailer
Trailer
right indicator
right indicator The left or right-hand trailer turn signal lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. b
Trailer brake lamp Trailer brake lamp The trailer brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself.
or
X Visit a qualified specialist workshop. b
Rear left indica‐ Rear left indica‐
tor tor
orRear right
Rear right
indicator
indicator The rear left-hand or rear right-hand turn signal is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Front left indica‐ Front left indica‐
tor tor
orFront right
Front right
indicator
indicator The front left-hand or front right-hand turn signal is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Left Left
mirror
mirror indica‐
indica‐
tor
tor orRight mir‐
Right mir‐
ror indicator
ror indicator The turn signal in the left-hand or right-hand exterior mirror is
faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Third brake lamp Third brake lamp The third brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. b
Left-hand tail Left-hand tail
lamp/brake lamp/brake
lamp lamporRight-hand
Right-hand
tail lamp/brake
tail lamp/brake
lamp lamp The left or right-hand tail lamp/brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 118).
or
X Visit a qualified specialist workshop. Display
messages
261On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions b
Intell. Light Sys‐ Intell. Light Sys‐
tem inoperative tem inoperative The Intelligent Light System is faulty. The lights remain available
without the Intelligent Light System.
X
Visit a qualified specialist workshop. b
Malfunction See Malfunction See
Owner's Manual Owner's Manual The exterior lighting is faulty.
X
Visit a qualified specialist workshop. Vehicles with trailer tow hitch: a fuse may have blown.
X
Check the fuses (Y page 346).
X If necessary, replace the blown fuse. Observe the warning notes
as you do so.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. b
AUTO AUTO
lights
lights inoper‐
inoper‐
ative
ative The light sensor is faulty.
X
Visit a qualified specialist workshop. b
Switch off lights Switch off lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã.Adaptive Adaptive
Main-beam
Main-beam
Assist inoperative
Assist inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Adaptive
Main-beam
Main-beam
Assist currently
Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual Adaptive Highbeam Assist is deactivated and temporarily inoper-
ative. Possible causes:
R
the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
X Clean the windscreen.
If the system detects that the camera is fully operational again,
the Adaptive Main-beam Assist available again Adaptive Main-beam Assist available again message
is displayed.
Adaptive Highbeam Assist is operational again. Display
messages
263On-board computer and displays Z

Safety systems
Problem Possible causes/consequences and
M
MSolutions J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
The braking efficiency may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 164).
X Do not top up the brake fluid. Topping up will not rectify the
fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. !
The yellow ABS warning
lamp is lit while the
engine is running.
ABS (Anti-lock Brake System) has been deactivated due to a fault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP
®
(Electronic
Stability Program), PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit 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 trans-
mission, will not be available. 286
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running.
ABS is temporarily unavailable. Therefore, BAS, BAS PLUS, ESP
®
,
EBD (electronic brake force distribution), PRE-SAFE ®
,
PRE-SAFE ®
Brake, the HOLD function, hill start assist, the adaptive
brake lights and ESP ®
trailer stabilisation, for example, are also
deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is a risk of an accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
287On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds.
EBD is not available due to a malfunction. Therefore, ABS, BAS,
BAS PLUS, ESP
®
, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation, for example, are not available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. J֌!
The red brake warning
lamp, the yellow ESP
®
and ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. ABS and ESP
®
are not available due to a fault. Therefore, BAS, BAS
PLUS, EBD, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD function, hill
start assist, the adaptive brake lights and ESP ®
trailer stabilisa-
tion, for example, are not available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 288
Warning and indicator lamps in the instrument clusterOn-board computer and displays