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
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
ProblemPossible causes/consequences andMSolutions
?
The red coolant
warning lamp is lit
while the engine
is running.The coolant temperature is too high.
XStop the vehicle as soon as possible, paying attention to road and
traffic conditions.
XConsult a qualified specialist workshop.
?The red coolant
warning lamp is lit
while the engine
is running.The coolant temperature is too high.
If the vehicle is stopped after being subjected to extreme loads, the
coolant warning lamp may come on when the ignition is switched on
or the engine is restarted. Such loads can be, for example, driving in
mountainous terrain or driving with a trailer.
XRun the engine for approximately 1 minute at idling speed.
XConsult a qualified specialist workshop if the display message con-
tinues to be shown.
7
|The yellow
reserve fuel warn-
ing lamp is on. At
the same time,
0
appears in the
fuel tank content
display while the
engine is running,
although there is
fuel in the fuel
tank.
The fuel filler cap is not closed.
XClose the fuel filler cap.
You will hear a click when the fuel filler cap is closed fully.
XIf the malfunction continues to be displayed, have it rectified imme-
diately at a qualified specialist workshop.
;
The yellow Check
Engine indicator
lamp is lit up or
flashes while the
engine is running.You have used up all fuel in the tank.
The engine is running in emergency mode.
XRefuel at the nearest gas station (Ypage 124).
XBleed the fuel system (Ypage 120).
XStart the engine three to four times in succession after refueling.
Emergency running mode will be canceled. The vehicle does not
need to be checked.
;The yellow Check
Engine indicator
lamp is lit up or
flashes while the
engine is running.The injection control is malfunctioning.
The engine is running in emergency mode.
Engine power output may be reduced.
XHave the vehicle checked at a qualified specialist workshop as soon
as possible.
In some states it is legally prescribed that after the Check Engine
indicator lamp lights up you must contact a qualified specialist work-
shop immediately. Observe the legal requirements.
196Indicator and warning lamps in the instrument cluster
On-board computer and displays
When handling, storing and disposing of fuels,
please observe the relevant regulations.
Tank contents
Depending on equipment, the total capacity of
the fuel tank may vary.
Vehicle typeTotal capa-cityof which
reserve fuel
2500
3500Approx-imately
26.4 US gal (100 l)Approx-
imately
5.0 US gal
(19 l)
All-wheel-
drive vehi-
clesApprox-
imately
24.6 US gal (93 l)
Diesel
Fuel grade
GWARNING
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline with diesel fuel.
!Filter the fuel before transferring it to the
vehicle if you are refueling the vehicle from
barrels or containers.
This will prevent malfunctions in the fuel sys-
tem due to contaminated fuel.
!You will damage the diesel engine if you do
not refuel with ULSD or a diesel fuel with a
sulfur content of more than 15 ppm.
!Do not use the following:
Rmarine diesel
Rheating oil
Rvegetable oil
Rgasoline
Rparaffin
Rkerosene
Do not mix such fuels with diesel fuel and do
not use any special additives. This can other- wise lead to engine damage. This does not
include flow improvers. For further informa-
tion, see "Flow improvers".
Usually you will find information about the fuel
grade on the filling pump. If there is no identifi-
cation on the filling pump, consult a gas station
attendant.
For more information about refueling
(
Ypage 124).
Diesel at very low outside temperatures
GWARNING
If you heat fuel system components, e.g. with
a hot-air gun or open flame, these compo-
nents could be damaged. This can cause fuel
to escape and ignite. Depending on the type
of damage, fuel may also not escape until the
engine is running. There is a risk of fire and
explosion.
Never heat fuel system components. Contact
a qualified specialist workshop to rectify the
malfunction.
Refill only with commercially available ULTRA-
LOW SULFUR DIESEL (ULSD, maximum sulfur
content 15 ppm), which fulfills the ASTM D975
standard.
The flow properties of diesel may be inadequate
at low outside temperatures due to paraffin sep-
aration.
iMalfunctions resulting from paraffin sepa-
ration can only be rectified by heating the
entire fuel system. Park the vehicle in a
heated garage, for example.
To prevent operating problems, diesel with bet-
ter flow qualities is available during the winter
months. You can obtain information at the gas
station or from your fuel supplier.
Your vehicle is equipped with a fuel preheating
system. This improves the flow properties of the
diesel by approximately 14.5 ‡ (8 †). ULTRA-
LOW SULFUR DIESEL can be used without ris k
o
f malfunction down to an outside temperature
of approximately 14 ‡ ( Ò10 †).
Fuel additives
!Do not add gasoline or kerosene to diesel
fuel to improve its flow characteristics. Gas-
oline or kerosene impairs the lubricating
properties of the diesel fuel. This can result in
274Service products and capacities
Technical data