If the supply of DEF falls below the reserve range
of 0.8 US gal (3.0l)the StArtS RExxmessage
appears in the display. Also, the yellow å
DEF indicator lamp lights up in the instrument
cluster and three warning tones sound.
In the display, xx
corresponds to the number of
possible remaining engine starts ( 16to0).
When the display shows that the number of
remaining starts is 0
, theStArtSIdLEmessage
appears in the display and three warning tones
sound.
In addition, the yellow åDEF indicator lamp
and the ;Check Engine indicator lamp light
up in the instrument cluster and three warning
tones sound.
The engine management only allows speeds of
up to 5 mph (8 km/h).
Add at least 1.5 US gal (5.5 l) of DEF
(
Ypage 126).
The display message only disappears when the
vehicle is stationary, at the latest after
20 second s, as soon as yo uswit ch on the igni-
tion or start the engine after refueling.
Vehicles with steering wheel buttons
If the supply of DEF is less than 1.5 US gal
(5.5 l),the Check Diesel Exhaust Fluid
See Operator's Manualmessage appears in
the display.
If the supply of DEF falls below the reserve range
of 0.8 US ga l(3.0 l),the XX
startsremainingmessage is displayed.
Three short warning tones also sound.
In the display, xx
corresponds to the number of
possible remaining engine starts ( 16to0).
When the display shows that the number of
remaining starts is 0
, theStArtSIdLEmessage
appears in the display.
The yellow ;Check Engine indicator lamp
also lights up and three short warning tones
sound.
The engine management only allows speeds of
up to 5 mph (8 km/h).
Add at least 1.5 US gal (5.5 l) of DEF
(
Ypage 126).
The display message only disappears when the
vehicle is stationary, at the latest after
20 seconds, as soon as you switch on the igni-
tion or start the engine after refueling.
On-board computer (vehicles without
steering wheel buttons)
Operating the on-board computer
General notes
The on-board computer is activated as soon as
you turn the key to position 1in the ignition lock.
The on-board computer shows vehicle informa-
tion and settings in the display.
You can control the display and the settings in
the on-board computer using the adjustment
buttons on the instrument cluster.
Standard display
:Odometer
;Trip odometer
=Clock
?Outside temperature or digital speedometer
AFuel gage (Ypage 159)
BSelector lever position or current shift range
with automatic transmission (Ypage 121)
XTo call up the standard display: turn the key
to position 2in the ignition lock.
XPress the 4menu button for longer than
1 second.
The information shown in the display changes
from the outside temperature to the digital
speedometer.
Menus in the on-board computer
Overview
If you wish to exit a menu and go to the standard display:
XPress the 4menu button for longer than
1 second.
or
XDo not press any button for 10 seconds.
The display accepts the changed settings.
160On-board computer (vehicles without steering wheel buttons)
On-board computer and displays
Using thef,g,4or9 adjustment buttons,
you can select the following functions:
RCalling up the service due date
(Ypage 222)
RChecking the oil level (Ypage 216)
RChecking the DEF supply (Ypage 159)
RPreselecting/setting the auxiliary heating
switch-on time (Ypage 107)
RTire pressure monitor(Ypage 249)
RSetting the time (Ypage 161)
RActivating/deactivating Highbeam Assist
(Ypage 168)
RSetting the daytime running lamps
(Ypage 80)
Setting the time
XTurn the SmartKey to position 2in the ignition
lock.
XPress the 4menu button repeatedly until the
hours figure flashes.
XPress the forg button to set the hour.
XPress the 9reset button.
The minute display flashes.
XPress the forg button to set the minute.
iIf you keep the forg button pressed, the
value will change continuously.
Activating/deactivating Highbeam
Assist
XTurn the SmartKey to position 2in the ignition
lock.
XPress the 4menu button repeatedly until the
_ indicator lamp flashes and the onorOFFmessage appears in the display.
XUse the forg button to switch Highbeam
Assist on/off.
Switching the daytime running lamps
on/off
If you switch the daytime running lamps on, the
daytime running lamps will automatically light
up when the engine is running.
For safety reasons, it is only possible to change
this setting when the vehicle is stationary. The
factory setting is on
in countries where daytime
running lamp mode or daytime running lamps
are mandatory.
XTurn the SmartKey to position 2in the ignition
lock.
XPress the 4menu button repeatedly until the
L indicator lamp flashes and the onorOFFmessage appears in the display.
XPress the forg button to activate or deac-
tivate the daytime running lamps.
iUSA only:
If you turn the light switch to TorL,
the corresponding light switches on. If you
turn the light switch to Ã, the daytime
running lamps remain switched on.
Canada only:
If you turn the light switch to L, the low-
beam headlamps switch on. If you turn the
light switch to TorÃ, the daytime run-
ning lamps remain switched on.
On-board computer (vehicles with
steering wheel buttons)
Operating the on-board computer
Overview
XTo activate the on-board computer: turn
the key to position 1in the ignition lock.
The on-board computer shows vehicle informa-
tion and settings in the display.
You can control the display and the settings in
the on-board computer with the buttons on the
steering wheel.
On-board computer (vehicles with steering wheel buttons)161
On-board computer and displays
Z
Menu overview
Diagrams
This is what the displays look like when you scroll through the menus.
Generic terms
The illustration shows the menus on a vehicle
with Audio 15.
On Sound 5/Audio 20, the on-board computer
always shows the AUDIOandTEL (telephone)
menus in English. This is the case even if a dif-
ferent language is selected for the display.
Operation
:Operation menu (Ypage 163)
RStandard display
RCalling up the service due date
(Ypage 222)
RTire pressure monitor (Ypage 249)
RChecking the engine oil level
(Ypage 216)
;Audio menu (Ypage 164)
=Message memory menu (Ypage 173)
?Settings menu (Ypage 165)
ATrip computer menu (Ypage 171)
BTelephone menu (Ypage 172)
iThe generic terms in the tabular overview
should make orientation easier for you. How-
ever, they are not always shown on the dis-
play.
Operation menu
Overview
You can select the following functions in the
Operation menu by pressing the 9or:
button on the steering wheel:
RDisplaying the trip odometer and odometer
(standard display) (Ypage 164)
RDisplaying the coolant temperature
(Ypage 164)
RCalling up the service due date
(Ypage 222)
RTire pressure monitor (Ypage 249)
RChecking the oil level (Ypage 216)
On-board computer (vehicles with steering wheel buttons)163
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
dEF ChkIn addition,th eyellow åDEFindicator lamp lights up in th einstru-
men tcluste rand awarning tone sounds.
The DE Fsupply has dropped belo w1.5US gal (5.5l).
XAdd DEF supply (Ypage 126).
The å DEF indicator lamp only disappears when the vehicle is
stationary, at the latest after 20 secondsa s soon as you switch on
the ignition or start the engine after refueling.
In addition, the yellow ;Check Engine indicator lamp and the yel-
low å DEF indicator lamp light up in the instrument cluster and a
warning tone sounds.
The DEF reducing agent is contaminated, diluted or is not compliant
with ISO 22241.
XHave the DEF tank cleaned and refilled at a qualified specialist
workshop as soon as possible.
StArtS RExxIn addition, the yellow åDEF indicator lamp lights up and a warning
tone sequence sounds.
The DEF supply has dropped below the 0.8 US gal (3.0 l) reserve mark.
After the message appears for the first time, the remaining DEF supply
will last for approximately 1200 miles (1900 km). The engine can then
only be started another 16 times.
The number of remaining engine starts XX
(16to1) is shown in the
message every time the engine is started.
XAdd at least 1.5 US gal (5.5 l) of DEF (Ypage 126).
The å DEF indicator lamp disappears after no more than
20 seconds after the vehicle has stopped or you have switched on the ignition or started the engine after refueling.
In addition, the yellow ;Check Engine indicator lamp and the yel-
low å DEF indicator lamp light up in the instrument cluster and
three short warning tones sound.
The DEF reducing agent is contaminated, diluted or is not compliant
with ISO 22241.
The exhaust gas aftertreatment is malfunctioning or an emission rel-
evant malfunction has occurred. This malfunction or defect can dam- age the exhaust gas aftertreatment.
XVisit a qualified specialist workshop immediately.
¯
StArtS IdLE
In addition, the yellow åDEF indicator lamp and the ;Check
Engine indicator lamp light up in the instrument cluster and three
warning tones sound.
If the StArtS
IdLEmessage is displayed, you cannot drive the vehicle
at a speed exceeding 5 mph (8 km/h).
XAdd at least 1.5 US gal (5.5 l) of DEF (Ypage 126).
The å DEF indicator lamp disappears after no more than
20 seconds after the vehicle has stopped or you have switched on the ignition or started the engine after refueling.
Display messages175
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
Highbeam AssistinoperativeHighbeamAssis tis faulty.
XVisit aqualified specialist workshop .
HighbeamAssisttem‐porarily unavaila‐ble
Highbea mAssis tis deactivated and temporarily inoperative.
Possibl ecauses are:
RThe camera' sfunctionalit yis impaire ddue to heav yrain ,snow or
fog .
RThe windshield is dirty in th ecamera' sfield of vision .
XStop thevehicl epayin gattention to roa dand traffic conditions.
XSecur eth evehicl eto preven tit from rollin gaway (Ypage 127).
XClean th ewindshield (Ypage 231), particularly in th ecamera' s
field of vision .
If th emalfunction has been rectified, th eHighbeam Assist
available againmessage appears.
Engine
Display messagesPossible causes/consequences and MSolutions
Check DieselExhaustFluid SeeOperator' sManual
The DE Fsupply has dropped belo w1.5US gal (5. 5l).
XAd dDE Fsupply (Ypage 126).
The display message only disappear swhen th evehicl eis stationary,
at th elatest after 20 seconds, as soo nas you switch on th eignition
or start th eengin eafter refueling.
å
XX starts remaining
Three short warning tone salso sound.
Afte rth emessage appear sfor th efirst time, th eremaining DE Fsupply
will last for approximately 1200 mile s(1900 km). The engin ecan then
only be started another 16 times .
The number of remaining engin estart sxx
(16to 0)is shown in th e
message every time th eengin eis started.
XAd dat least 1. 5US gal (5.5l)of DEF (Ypage 126).
å
Idle Mode
The yellow ;Check Engine indicator lamp also lights up and three
short warning tones sound.
You cannot drive the vehicle at a speed exceeding 5 mph (8 km/h).
XAdd at least 1.5 US gal (5.5 l)of DEF (Ypage 126).
The display message and the yellow ;Check Engine indicator
lamp only disappear when the vehicle is stationary, at the latest
after 20 seconds as soon as you switch on the ignition or start the
engine after refueling.
Check DieselExhaust Fluid SeeOperator's Manual
In addition, the yellow ;DEF indicator lamp lights up and a warning
tone sounds.
The DEF reducing agent is contaminated, diluted or is not compliant
with ISO 22241.
XHave the DEF tank cleaned and refilled at a qualified specialist
workshop as soon as possible.
184Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
å
XX starts remaining
The yellow; CheckEngin eindicator lamp also lights up and three
short warning tone ssound.
Afte rth emessage appear sfor th efirst time, th eremaining DE Fsupply
will last for approximately 1200 mile s(1900 km). The engin ecan then
only be started another 16 times .
The number of remaining engin estart sxx
(16to 0)is shown in th e
message every time th eengin eis started.
The DE Freducin gagen tis contaminated, diluted or is no tcomplian t
wit hIS O 22241.
The exhaust gas aftertreatmen tis malfunctioning or an emission rel -
evan tmalfunction has occurred .This malfunction or defec tcan dam-
age th eexhaust gas aftertreatment.
XVisit aqualified specialist workshop immediately.
å
Idl eMod e
The yello w; CheckEngin eindicator lamp also lights up and three
short warning tone ssound.
The vehicl ecanno tbe driven at aspeed exceedin g 5mph (8 km/h).
XVisit aqualified specialist workshop immediately.
?
Coolan tStop, tur nengine off
The coolanttemperature is to ohigh .
If th evehicl eis stoppe dafter bein gsubjecte dto extreme loads ,th e
coolan twarning lamp may come on when th eignition is switched on
or th eengin eis restarted. Suc hloads can be, for example, drivin gin
mountainous terrain or drivin gwit h a trailer .
XRun th eengin efor approximately 1minute at idlin gspeed.
XConsult aqualified specialist workshop if th edisplay message con-
tinue sto be shown.
*
Check coolan tlevel
The coolan tlevel is to olow.
Never run th eengin eif th ecoolan tlevel is to olow. The engin ecould
overheat and be damaged.
XStop th evehicl eas soo nas possible, payin gattention to roa dand
traffic conditions.
XSwitc hoff th eengin eand let it cool down .
XAddcoolan tand be sur eto observ eth ewarning note s
(Ypage 280).
XIf you need to add coolan tfrequently, hav eth eengin ecoolin gsys-
te m checke dat aqualified specialist workshop .
7
Reservefue lDriveto agas statio n
The fuel level has fallen int oth ereserv erange.
XRefue lat th eneares tgas station (Ypage 124).
:
WaterinfuelVisitworkshop
The water that has collecte din th ewater separator has reached th e
maximum level.
XDrain th ewater separator (Ypage 220).
Display messages185
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
m
Fuelfilter Visitworkshop
The fuel filter is dirty.
XHav eth efuel filter elemen treplace das soo nas possibl eat aquali-
fie dspecialist workshop .
4
Engine oil Add 1.0quart(Canada: 1.0liter)
The oil level is toolow.
XChec kth eoil level th enext time you refuel (Ypage 216), and add
oil.
4
Engine oil levelNot whe neng .run ‐ning
You wan tto chec kth eengin eoil level eve nthough th eengin eis still
running.
XSwitc hoff th eengine.
XChec kth eoil level (Ypage 216).
4
Engine oil levelReduce oil level
You haveadded to omuc hengin eoil. There is aris kof damaging th e
engin eor catalytic converter.
XChec kth eoil level (Ypage 216).
XIf theoil level is to ohigh :hav eth eengin eoil extracted at th enext
qualified specialist workshop .
XIf theoil level is correct: hav eth emalfunction rectifie dat th enext
qualified specialist workshop .
4
Engine oil levelStop, turnengineoff
There is no tenough or no oil in th eengine. There is adanger of engin e
damage.
XStop th evehicl eas soo nas possible, payin gattention to roa dand
traffic conditions.
XChec kth eoil level wit hth eoil dipstick (Ypage 217).
XIf theengin eoil level is correct: hav eth emalfunction rectifie d
immediately at aqualified specialist workshop .
XIf theengin eoil level is to olow: hav eth evehicl etowed to aqualified
specialist workshop .
4
Oil sensor Visitworkshop
There isamalfunction in th eengin eoil level display.
XHav eth evehicl echecke dimmediately at aqualified specialist
workshop .
Driving systems
Display messagesPossible causes/consequences and MSolutions
_ _ _
Cruise control
The activation condition sfor cruise control hav eno tbeen met .
You can only activat ecruise control from speeds of 20 mph
(30 km/h).
Cruise contro l
Visit workshop
Cruisecontrol has been deactivated due to amalfunction .
XHavecruise control checke dat aqualified specialist workshop .
186Display messages
On-board computer and displays
ProblemPossible causes/consequences andMSolutions
b
The red brake sys-
tem indicator
lamp is lit while
the engine is run-
ning.There is insufficient brake fluid in the expansion tank.
GWARNING
Braking performance can be impaired.
There is a risk of an accident.
XVehicles with steering wheel buttons: also observe the messages in
the display (Ypage 173).
XStop the vehicle as soon as possible, paying attention to road and
traffic conditions.
XCheck the brake fluid level in the expansion tank (Ypage 219).
XIf the brake fluid is below the MIN mark: do not drive on!
XDo not add brake fluid. This does not solve the problem.
XConsult a qualified specialist workshop.
b When towing a
trailer: the red
brake system
indicator lamp is
lit while the
engine is running.
Additionally, a
warning tone
sounds.GWARNING
The brake force booster in the trailer is faulty.
The driving and braking characteristics of your vehicle could change.
There is a risk of the trailer overbraking and of you losing control over
the truck/trailer combination.
There is a risk of an accident.
XVehicles with steering wheel buttons: also observe the messages in
the display (Ypage 173).
XStop the vehicle as soon as possible, paying attention to road and
traffic conditions.
XDo not drive on.
XConsult a qualified specialist workshop.
: The yellow
ASR/BAS indica-
tor lamp is lit
while the engine
is running.ASR has been deactivated due to a malfunction.
The engine power output may be reduced.
GWARNING
The driven wheels can spin when accelerating.
There is an increased risk of skidding and accidents.
XDrive on with care.
XConsult a qualified specialist workshop as soon as possible.
: The yellow
ASR/BAS indica-
tor lamp is lit
while the engine
is running.BAS has been deactivated due to a malfunction.
GWARNING
The brake system continues to function normally, but without elec-
tronic support.
The braking distance can increase in emergency braking situations.
There is a risk of an accident.
XDrive on with care.
XVisit a qualified specialist workshop immediately.
192Indicator and warning lamps in the instrument cluster
On-board computer and displays