Engine
Display messagesPossible causes/consequences andMSolutions
+
CheckCoolantLevelSee Operator's Man‐ual
The coolant level is too low.
!Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
XAdd coolant, observing the warning notes before doing so
(Ypage 256).
XIf you need to add coolant more often than usual, have the engine
coolant system checked at a qualified specialist workshop.
?The fan motor is faulty.
XAt coolant temperatures below 248 ‡(120 †), drive to the nearest
qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic.
?
Coolant Too HotStop Vehicle TurnEngine Off
The coolant is too hot.
A warning tone also sounds.
GWARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to catch
fire.
Steam from the overheated engine can also cause serious burns which
can occur just by opening the hood.
There is a risk of injury.
XPull over and stop the vehicle safely and switch off the engine, pay- ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 138).
XWait until the engine has cooled down.
XMake sure that the air supply to the engine radiator is not blocked,e.g. by snow, slush or ice.
XDo not start the engine again until the display message goes out and
the coolant temperature is below 248 ‡ (120 †). Otherwise, the
engine could be damaged.
XPay attention to the coolant temperature display.
XIf the temperature increases again, visit a qualified specialist work-
shop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †).
Display messages207
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
The HOLD function is deactivated. Whenth ebrak epedal is firmly
depressed, an activation condition is no tfulfilled .
A warning tone also sounds.
XChec kth eactivation condition sfor th eHOLD function
(Ypage 156).
Lan eKeepin gAssistCurrently Unavaila‐ble See Operator' sManualorActive Lan eKeepingAssist Cur ‐rently UnavailableSee Operator' sMan ‐ual
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis deactivated and
temporarily inoperative.
Possibl ecauses are:
Rth ewindshield in th ecamera' sfield of vision is dirty.
Rvisibilit yis impaire ddue to heav yrain ,snow or fog .
Rthere havebeen no lan emarking sfor an extended period.
Rth elan emarking sare worn, dark or covered, e.g. by dir tor snow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Lan eKeepin gAssis tor Active Lan eKeepin gAssis tis operational
again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 138).
XClean th ewindshield.
Lan eKeepin gAssistInoperativeorActiveLan eKeepin gAssistInoperative
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis defective.
XVisit aqualified specialist workshop .
Blind SpotAssistCurrently Unavaila‐ble See Operator' sManualorActiveBlind Spo tAssistCurrently Unavaila‐ble See Operator' sManual
Blind Spot Assistor Active Blind Spot Assis tis temporarily inoperative.
Possibl ecauses are:
Rth eradar sensor system is outside th eoperating temperature
range.
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
The yellow 9indicator lamp salso ligh tup in th eexterio rmirrors.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Blind Spot Assis tor Active Blind Spot Assis tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 138).
XRestart th eengine.
210Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
Blind SpotAssistInoperativeorActiveBlind Spo tAssistInoperative
Blind Spot Assis tor Active Blind Spot Assis tis defective.
The yellow 9indicator lamp salso ligh tup in th eexterio rmirrors.
XVisit aqualified specialist workshop .
ParkAssistCanceledThe driver's door is open and th edriver's seat belt has no tbeen fas -
tened.
XRepeat th eparking process wit hth eseat belt fastene dand th e
driver's door closed .
You haveinadvertentl ytouched th emultifunction steering whee lwhile
steering intervention was active .
XWhilesteering intervention is active ,mak esur ethat th emultifunc-
tion steering whee lis no ttouched unintentionally.
The vehicl ehas started to skid and ES P®has intervened.
XUse Active Parking Assistagain later (Ypage 161).
ParkAssist Inoper ‐ativeYou havejus tcarrie dout alarg enumber of turnin gor parking maneu-
vers.
Active Parking Assis twill become available again after approximately
te nminute s (
Ypage 161).
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSwitc hoff and restar tth eengine.
If th emultifunction display still shows th edisplay message :
XVisitaqualified specialist workshop .
PARKTRONICis defective.
XVisit aqualified specialist workshop .
ParkAssistFinishedThe vehicl eis parked. Awarning tone also sounds.
The display message disappear sautomatically.
DISTRONIC PLU SOffDISTRONI CPLU Shas been deactivated.
If awarning tone also sounds, DISTRONI CPLU Shas deactivated auto -
matically (
Ypage 147)
DISTRONIC PLU SNowAvailableDISTRONI CPLU Sis operational again after having been temporarily
unavailable .You can no wreactivat eDISTRONI CPLU S (Ypage 147).
Display messages211
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
DISTRONIC PLUSCur ‐rently UnavailableSee Operator' sMan ‐ual
DISTRONI CPLU Sis temporarily inoperative.
Steering Assis tand Stop&Go Pilo tare temporarily inoperative.
Possibl ecauses are:
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
Rthesystem is outside th eoperating temperature range.
Rth eon-boar dvoltag eis to olow.
A warning tone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
DISTRONI CPLU Sis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 138).
XRestart th eengine.
DISTRONICPLU SInop‐erativ eDISTRONI CPLU Sis defective.
The followin gmay hav ealso failed:
RBA SPLU Swit hCross-Traffic Assis t
RPRE-SAFE®Brake
RSteering Assis tand Stop&Go Pilo t
A warning tone also sounds.
XVisit aqualified specialist workshop .
DISTRONIC PLUSSus ‐pendedYou hav edepressed th eaccelerato rpedal .DISTRONI CPLU Sis no
longer controllin gth espeed of th evehicle.
XRemove your foo tfrom th eaccelerato rpedal .
DISTRONIC PLU S
- - -mph
An activation condition for DISTRONI CPLU Sis no tfulfilled .
XCheckth eactivation condition sfor DISTRONI CPLU S (Ypage 147).
212Display messages
On-board computer and displays
Tires
Display messagesPossible causes/consequences andMSolutions
Correct
Tire Pressure
The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
XCheck the tire pressures at the next opportunity (Ypage 287).
XIf necessary, correct the tire pressure.
XRestart the tire pressure monitor (Ypage 289).
Check
Tires
The tire pressure in one or more tires has dropped significantly. The
wheel position is shown in the multifunction display.
A warning tone also sounds.
GWARNING
Tire pressures that are too low pose the following hazards:
Rthey may burst, especially as the load and vehicle speed increase.
Rthey may wear excessively and/or unevenly, which may greatly
impair tire traction.
Rthe driving characteristics, as well as steering and braking, may be
greatly impaired.
There is a risk of an accident.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
XSecure the vehicle against rolling away (Ypage 138).
XCheck the tires and, if necessary, follow the instructions for a flat
tire (Ypage 266).
XCheck the tire pressure (Ypage 287).
XIf necessary, correct the tire pressure.
Warning
Tire Malfunction
The tire pressure in one or more tires has dropped suddenly. The wheel
position is shown in the multifunction display.
GWARNING
Driving with a flat tire poses a risk of the following hazards:
Ra flat tire affects the ability to steer or brake the vehicle.
Ryou could lose control of the vehicle.
Rcontinued driving with a flat tire will cause excessive heat build-up
and possibly a fire.
There is a risk of an accident.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
XSecure the vehicle against rolling away (Ypage 138).
XCheck the tires and, if necessary, follow the instructions for a flat
tire (Ypage 266).
214Displa y messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
Â
Key Not Detected(reddisplay message )
The KEYLESS-GO ke yis no tin th evehicle.
A warning tone also sounds.
If th eengin eis switched off ,you can no longer loc kth evehicl ecen-
trally or start th eengine.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 138).
XLocate th eKEYLESS-GO key.
A stron gsource of radi owave sis causing interferenc eand this is
preventing th eKEYLESS-GO ke yfrom bein grecognized when th e
engin eis running.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 138).
XInsertth eSmartKey int oth eignition loc kand bring int oke ymode.
Â
Key Not Detected(whit edisplay message )
The KEYLESS-GO ke ycanno tbe detecte dat present.
XChange th elocation of th eSmartKey wit hth eKEYLESS-GO func-
tion sin th evehicle.
If th eKEYLESS-GO ke yis still no tdetected:
XOperat eth evehicl ewit hth eSmartKey in th eignition lock.
Â
Remove 'Start 'But ‐ton and Insert Key
The KEYLESS-GO ke ycan continuousl yno tbe detected.
KEYLESS-GO is temporarily malfunctioning or is defective. Awarning
tone also sounds.
XInser tth eSmartKey int oth eignition loc kand tur nit to th edesire d
position .
XVisitaqualified specialist workshop .
Warning and indicat orlamps in the instrume nt cluster
General notes
Some systems carry out aself-diagnosis when th eignition is switched on .Therefore ,som eindicator
and warning lamp smay ligh tup or flas htemporarily. This behavio ris non-critical .These indicator
and warning lamp sonly indicat e amalfunction if they ligh tup or flas hafter starting th eengin eor
whils tdriving.
Warning and indicator lamps in the instrument cluster219
On-board computer and displays
Z
Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system
Rin the fuel system
The emission limit values may be exceeded and the engine may be in emergency
mode.
XVisit a qualified specialist workshop immediately.
iIn some states, you must immediately visit a qualified specialist workshop as
soon as the yellow Check Engine warning lamp lights up. This is due to the legal
requirements in effect in these states. If in doubt, check whether such legal
regulations apply in the state in which you are currently driving.
8N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ;Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler cap.
XIf the fuel filler cap is closed:visit a qualified specialist workshop.
?NThe red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the scale.
The temperature sensor for the coolant temperature gage is defective.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 138).
XConsult a qualified specialist workshop.
Warning and indicator lamps in the instrument cluster225
On-board computer and displays
Z
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 138).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 256).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature is below 248 ‡
(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in mountainous terrain,
and stop-and-go traffic.
?N The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature has exceeded 248 ‡(120 †). The airflow to the engine
radiator may be blocked or the coolant level may be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some fluids which
may have leaked into the engine compartment to catch fire.
Steam from the overheated engine can also cause serious burns which can occur
just by opening the hood.
There is a risk of injury.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 138).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 256).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
226Warning and indicator lamps in the instrument cluster
On-board computer and displays