trailer MERCEDES-BENZ M-CLASS SUV 2011 Owner's Guide

X
To switc hthe conn ected powe rsupply
on or off: turn thekey in the ignition lock
to position 2or 0respectivel y. Bulb failure indi
cator for LE Dlamps
i If LED lamps are fitte dinthe trailer, an
error message ma yappear in the multi-
function display even if there is no fault. The
reason for the error message may be that
the current has fallen below the minimum
of 50 milliamper es(mA).
To ensure reliabl eoperation of the bul bfailure
indicator, each LED chai ninthe trailer lighting
must be guaranteed aminimum current of
50 mA. Trailer with 7-pin connector
Genera linforma tion If your trailer has
a7-pin connector, you can
connect it to the 13-pin socket on the ball
coupling using an adapter or, if necessary, an
adapter cable .Both of these can be obtained
at aq ualified specialist workshop, e.g. at a
Mercedes-Ben zService Centre.
Fitting the adapter X
Open the socket cover.
X Insert the connector with lug :into
groove ;on the socket and tur nthe con-
nec torc lockwise to the stop. X
Let the cover engage.
X If you are using an adapter cable, secure
the cable to the trailer with cable ties.
! Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering. Towing
atrailer
231Driving andparki ng Z

Problems wit
htrailer towing Problem Possible causes/consequences and
M Solutions
The released ball cou-
pling cannot be
engaged. X
Visit aqualified specialist workshop. The ball coupling does
not unlock, even
though:
R the vehicle is station-
ary.
R no trailer cable is
connected.
R the release knob to
unlock the ball cou-
pling has been pulled
for more than asec-
ond. The on-boar
dvoltage is insufficient.
X Start the engine.
If the ball coupling still does not unlock:
X Visit aqualified specialist workshop. 232
Towin
gatrailerDriving and parking

Safety systems
Display messages Possible causes/consequences and
M Solutions
!÷
currentl
yunavail‐ able See Owner's
Manual G
Ris
kofa ccident
ABS (Anti-lock Braking System), ESP ®
(Electronic Stability Pro-
gram), BAS (Brake Assist), PRE-SAFE ®
,t he HOL Dfunction, hill
start assis tand ESP ®
trailer stabilisation are temporarily not avail-
able.
The adaptive brake lights ,BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! warning lamps ligh tupin
the instrument cluster.
The self-diagnosis function might not be complete ,for example.
ATTENTION ASSIS Tisdeactivated.
The brak esystem continues to function normally, but without the
functions liste dabove. The wheels could therefore lock if you
brak ehard, for example.
X Carefully drive on asuitable stretch of road, making slight steer-
ing movements, at aspeed 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 aqualified specialist workshop. G
Risk of accident
ABS ,ESP ®
,B AS ,PRE-SAFE ®
,t he HOL Dfunction, hill start assist
and ESP ®
trailer stabilisation are temporarily not available.
The adaptive brake lights ,BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! warning lamps ligh tupin
the instrument cluster.
For example, the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions liste dabove. The wheels could therefore lock if you
brak ehard, for example.
X Drive on carefully.
If the display message disappears, the functions mentioned
above are available again. 254
Display messagesOn-board computer and displays

Displa
ymessages Possible causes/consequences and
M Solutions
If th
edisplay message continues to be displayed:
X Drive on carefully.
X Visit aqualified specialist workshop. !÷
in
operative See Owner'
sManual G
Risk of accident
ABS, ESP ®
,B AS ,PRE-SAFE ®
,t he HOL Dfunction ,hill start assist
and ESP ®
trailer stabilisation are no tavailab ledue to amalfunc-
tion.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
als oh ave failed.
In addition, the J,÷,åand! warning lamp slight
up in the instrument cluster.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefor elock if you
brake hard, for example.
ATTENTION ASSIS Tisd eactivated.
X Drive on carefully.
X Visit aquali fieds pecialist workshop immediately. ÷
currentl
yunavail‐ able See Owner's
Manual G
Ris
kofa ccident
ESP ®
,B AS, PRE- SAFE ®
,t he HOL Dfunction, hill start assis tand
ESP ®
trailer stabilisation are temporarily not available.
The adaptive brake lights ,BAS PLU Sand PRE-SAFE ®
Brak emay
also have failed.
In addition, the ÷andå warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIS Tisdeactivated.
The brak esystem continues to function normally, but without the
functions liste dabove.
X Carefull ydrive on asuitable stretc hofroad, makin gslight steer-
ing movements, at aspeed above 20 km/h.
If the display message disappears, the fun ction sm entioned
above are available again.
If the display message continues to be displayed:
X Driv eonc arefully.
X Visit aqualified specialist workshop. Display messages
255On-boardcomputer and displays Z

Displa
ymessages Possible causes/consequences and
M Solutions
÷
in
operative See Owner'
sManual G
Risk of accident
ESP ®
,B AS ,PRE-SAFE ®
,t he HOL Dfunction ,hill start assist and
ESP ®
trailer stabilisation are no tavailab ledue to amalfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
als oh ave failed.
In addition, the ÷andå warning lamp slight up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
X Driv eonc arefully.
X Visi taq ualifieds pecialist workshop. T!
÷
inoperativ
eSee Owner'
sManual G
Ris
kofa ccident
EB D( electroni cbrake force dist ribution) ,ABS ,ESP ®
,B AS, PRE-
SAFE ®
,t he HOL Dfunction, hill start assist and ESP ®
trailer stabi-
lisation are not available due to amalfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
als oh ave failed.
In addition, the ÷,åand! warning lamp slight up in
the instrument cluster and awarning tone sounds.
ATTENTION ASSIST is deactivated.
The brake system continue stofunction normally, but withou tthe
func tions listed above. The wheels coul dtherefore lock if you
brake hard, for example.
X Drive on carefully.
X Visit aqualified specialist worksho pimmediately. !
Release parking
brake Th
er ed ! indicator lam pflashes and awarning tone sounds.
Ac ondition for automatic release of the electric parkin gbrake is
not fulfill ed (Ypag e161).
Yo ua re driving wit hthe electric parkin gbrake appl ied.
X Release the electric parking brake manually. The red
!indicator lamp flashe sand aw arning tone sounds.
You are making an emergency stop using the electric parking
brake (Y page 161). 256
Display messagesOn-board computer and displays

Displa
ymessages Possible causes/consequences and
M Solutions
6
Re
ar centre mal‐ function Consult
workshop G
Risk of in
jury
SRS has malfunctioned at the rear centre. The 6warning lamp
als olights up in th einstrument cluster.
X Visi taqualified specialist workshop. 6
Left
windowbag mal‐
function Consult
workshop orR
ight windowba
gmalfunc‐ tion Consult work‐
shop G
Ris
kofi njury
There is amalfunction in the left-han dand/or right-han dwindow-
bag. The 6warnin glamp also lights up in the instrumen tclus-
ter.
X Visit aqualified specialist workshop. Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed. Displa
ymessages Possible causes/consequences and
M Solutions
b
Le
ft cornering light or
Right cor‐ nering light Th
eleft or right-hand cornering light is faulty.
X Chec kwhether you ar epermitted to change the bulb yourself
(Y page 113).
or
X Visit aqualified specialist workshop. b
Left dipped beam
or
Righ tdipped beam Th
eleft or right-hand dipped-beam headlamp is faulty.
X Check whether you are permitted to change the bulb yourself
(Y page 113).
or
X Visit aqualified specialist workshop. b
Traile
rleft tail lamp or
Trailer right tail lamp Th
eleft or right-hand trailer tail lam pisfaulty.
X Check whethe ryou ar epermitted to change the bulb yourself.
or
X Visit aqualified specialist workshop. b
Traile
rleft indi‐ cator or
Trailer right indicator Th
eleft or right-hand trailer tur nsignal lamp is faulty.
X Check whether you are permitted to change the bulb yourself.
or
X Visit aqualified specialist workshop. 262
Display messagesOn-board computer and displ
ays

Displa
ymessages Possible causes/consequences and
M Solutions
b
Ma
lfunction See Owner'
sManual Th
ee xter ior lighting is faulty.
X Visit aqualified specialist workshop. Vehicles with trailer tow hitch:
afuse may have blown.
X Check the fuses (Y page 352).
X If necessary, replac ethe blown fuse. Observe the warnin gnotes
as you do so.
If the display message continues to be displayed:
X Visit aqualified specialist workshop. b
AUTO
lights inoper‐
ative The light sensor is faulty.
X
Visit aqualified specialist workshop. b
Switch of
flights Th
elights are still switched on when you leave the vehicle. A
warnin gtonea lso sounds.
X Turn the light switc htoÃ. Adaptive Main-beam
Assist inoperative Adap
tive Highbea mAssist is faulty.
X Visit aqualified specialist workshop. Adaptive Main-beam
Assist currently
unavailabl
eSee Owner's Manual Adap
tive Highbea mAssist is deac tivated and temporarily inoper-
ati ve.P ossible causes:
R the windscreen is dir tyinthec amera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
X Clean the windscreen.
If the system detect sthat the cam era is fullyoperational again,
the Adaptive Main-bea mAssist availabl eagain message
is displayed.
Adap tive Highbea mAssist is operationa lagain. Displa
ymessages
265On-board comp uter and displays Z

Driving systems
Display messages Possible causes/consequences and
M Solutions
À
At
tention Assist: Drowsines
sdetec‐ ted Base
donspecific criteria, ATTENTION ASSIST has determined that
th ed river is tired or paying less attention. Awarning ton ealso
sounds.
X If necessary, tak eabreak.
During long journeys, tak eregular break singood tim esoyou get
enough rest. À
At
tention Assist inoperative ATTENTION ASSIST ha
sfailed.
X Visit aquali fieds pecialist workshop. Á
Please
reduce speed You can
notc hang ethe vehicle level. Possible causes:
R you ar edriving to ofast for the selected vehicle level.
R you are towing atrailer.
R thet railer-coupling socket is being used ,e.g. for abicycle rack.
X Driv emore slowly and then select the desire dvehicle level
again.
R Vehicles with the ON&OFFROA Dpackage (Y page 183)
R Vehicles with the AIRMATI Cpackage (Y page 189)
X Observ ethe notes ontowing atrailer (Y page 226). Á
Co
mpressor is cool‐
ing Yo
uh ave selected ahigher vehicle level. The compressor first
needs to cool down because of frequen tlevel changes.
X Driv einam anner appropriate for the curren tvehicle level.
X Make sure that ther eissufficien tground cle arance.
X Allow the compresso rtocool down.
When the compressor has cooled down, the display message
disappears. The vehicle then con tinues rising to the selected
level. Á
Malfunction AIRMATIC is faulty.
X
Drive as appropriate for the current vehicl elevel, but do not
exceed 80 km /h.
X Make sur ethat ther eissufficient ground clearance.
X Have the vehicle checked at aqualified specialist workshop. The Active Curve System is faulty. The vehicle's handling charac-
teristics may be affected.
X Do not exceed amaximum spee dof80k m/h.
X Have th evehicle checked at aqualified specialist workshop. Display messages
269On-boardcomputer anddispl ays Z

Displa
ymessages Possible causes/consequences and
M Solutions
Bl
indS potA ssist currently unavail‐
abl
eS ee Owner's Manual or
Ac tive Blind Spo
tAssist currently unavail‐
abl
eS ee Owner's Manual Blind Spot Assist or Active Blind Spot Assis
tist emporaril yinop-
erative .Possible causes:
R you have established the electrical con nectio nbetween the
trailer and your vehicle.
R the sensors are dirty.
R function is impaired due to heavy rai norsnow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
X Whe ntowing atrailer, con firm th edisplay message with a.
If you are drivin gwithout atrailer and th edisplay message does
not disappear:
X Pull over and stop the vehicle safely as soon as possible ,paying
attention to road and traffic conditions.
X Apply the electric parking brake.
X Clean the sensors (Y page 327).
X Restart the engine.
If the system detect sthat the sensor sare full yoperational, the
display message disappears.
Blin dSpot Assist or Active Blin dSpot Assist is operational again. Blin
dSpot Assist inopera‐
tive or
Active Blind Spot Assist inoper‐
ative Blind Spot Assist or Active Blind Spot Assist is faulty.
Th ey ellow 9indicator lamps also light up in the exterior mir-
rors.
X Visit aqualified specialist workshop. Park Assist
cancelled The driver'
sdoor is open and the driver' sseat belt has not been
fastened.
X Repeat the parking process with the seat belt fastened and the
driver' sdoor closed. You have inadvertently touched the multifunc
tion steerin gwheel
while steerin gintervention was active.
X While steerin gintervention is active, make sure that the multi-
function steerin gwheel is not touched. 274
Displa
ymessagesOn-board compu tera nd displays

Problem Possible causes/consequences and
M Solutions
J
The red brake system
warnin
glamp comes on
while the engine is run-
ning. Awarning tone
also sounds. G
Risk of accident
There is insufficient brake fluid in the fluid reservoir.
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 Apply the electric parking brake.
X Consult aqualified specialist worksho pimmediately.
X Observe th eadditiona ldisplay messages in the multifunction
display.
Do not top up the brake fluid. This does not correct the error. !
The yello
wABS warning
lamp is lit while the
engine is running. G
Risk of accident
ABS (Anti-lock Brake System) has bee ndeactivated due to afault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE-SAFE ®
,P RE-SAFE ®
Brake, the HOL Dfunc-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are also deactivated, for example.
The brake system continues to function normally, but without the
functions listed above. The wheel scould therefor elock if you
brake hard ,for example.
ATTENTION ASSIS Tisdeactivated.
X Observ ethe additiona ldispla ymessages in the multifunction
display.
X Drive on carefully.
X Visit aqualified specialist workshop.
If the ABS control unit is faulty, there is also apossibility that other
systems, such as the navigation system or the automatic trans-
mission ,will not be available. 286
Warning and indicator lamp
sinthe instrument clusterOn-board compute rand displays