MERCEDES-BENZ GLS SUV 2018 Owner's Manual

Display messagesPossible causes/consequences andMSolutions
Â
Key Not Detected(reddisplay message )
The SmartKey is 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 161).
XLocate th eSmartKey.
Becaus ethere is interferenc efrom astron gsource of radi owaves, th e
SmartKey is no tdetecte dwhils tth eengin 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 161).
XInsertth eSmartKey int oth eignition loc kand drive in SmartKey
mode.
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Remove 'Start 'But ‐ton and Insert Key
RThe SmartKey detection function has atemporar ymalfunction or is
faulty.
RThe SmartKey is continually undetected.
A warning 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 cluster279
On-board computer and displays
Z

Safety
Seat belts
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
üNAfter starting the engine, the red seat belt warning lamp lights up for 6 seconds.
The seat belt warning lamp reminds the driver and front passenger to fasten their
seat belts.
XFasten your seat belt (Ypage 48).
üN After starting the engine, the red seat belt warning lamp lights up. In addition, a
warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
XFasten your seat belt (Ypage 48).
The warning tone ceases.
üN The red seat belt warning lamp lights up after the engine starts, as soon as the
driver's or the front-passenger door is closed.
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt (Ypage 48).
The warning lamp goes out.
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out.
üN The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or front passenger has not fastened their seat belt. The vehicle is being driven faster than 15 mph (25 km/h) or has briefly been driven faster than 15 mph
(25 km/h).
XFasten your seat belt (Ypage 48).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. The vehicle is being driven faster
than 15 mph (25 km/h) or has briefly been driven faster than 15 mph (25 km/h).
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out and the intermittent warning tone ceases.
280Warning and indicator lamps in the instrument cluster
On-board computer and displays

Safety systems
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
J$N$ (USA only), J(Canada only): the red brake system warning lamp is lit
while the engine is running.
A warning tone also sounds.
GWARNING
The brake boosting effect is malfunctioning and the braking characteristics may be
affected.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 161).
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction display.
J$N $ (USA only), J(Canada only): the red brake system warning lamp is lit
while the engine is running.
A warning tone also sounds.
GWARNING
There is not enough brake fluid in the brake fluid reservoir.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 161).
XDo not add brake fluid. Adding more will not correct the malfunction.
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction display.
$N USA only: the red brake system warning lamp is lit while the engine is running.
The multifunction display also shows a display message with the #symbol.
The brake pads/linings have reached their wear limit.
XVisit a qualified specialist workshop.
Warning and indicator lamps in the instrument cluster281
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
!NThe yellow ABS warning lamp is lit while the engine is running.
ABS (Anti-lock Braking System) is deactivated due to a malfunction.
Other driving systems and driving safety systems may also malfunction.
In addition, the ÷andå warning lamps may light up in the instrument
cluster.
ATTENTION ASSIST is deactivated.
GWARNING
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 affected. The braking
distance in an emergency braking situation can increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
If the ABS control unit is faulty, there is also a possibility that other systems, such
as the navigation system or the automatic transmission, will not be available.
282Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
!NThe yellow ABS warning lamp is lit while the engine is running.
ABS is temporarily unavailable.
Other driving systems and driving safety systems may also malfunction.
In addition, the ÷andå warning lamps may light up in the instrument
cluster.
ATTENTION ASSIST is deactivated.
Possible causes are:
Rself-diagnosis is not yet complete
Rthe on-board voltage may be insufficient
GWARNING
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 exam-
ple.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is a risk of an accident.
XCarefully drive a suitable distance, making slight steering movements at a speed
above 12 mph (20 km/h).
The functions mentioned above are available again when the warning lamp goes
out.
If the warning lamp is still on:
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
Warning and indicator lamps in the instrument cluster283
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
!NThe yellow ABS warning lamp is lit while the engine is running.
EBD is not available due to a malfunction.
Other driving systems and driving safety systems may also malfunction.
In addition, the ÷andå warning lamps may light up in the instrument
cluster.
ATTENTION ASSIST is deactivated.
GWARNING
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 exam-
ple.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
$J
֌
!N $ (USA only), J(Canada only): the red brake warning lamp and the yellow
ESP®, ESP®OFF and ABS warning lamps are lit while the engine is running.
ABS and ESP®are malfunctioning.
Other driving systems and driving safety systems may also malfunction.
ATTENTION ASSIST is deactivated.
GWARNING
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 exam-
ple.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
284Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
÷NThe yellow ESP®warning lamp flashes while the vehicle is in motion.
ESP®or traction control has intervened because there is a risk of skidding or at
least one wheel has started to spin.
Cruise control or Distance Pilot DISTRONIC is deactivated.
XWhen pulling away, only depress the accelerator pedal as far as necessary.
XEase off the accelerator pedal while the vehicle is in motion.
XAdapt your driving style to suit the road and weather conditions.
XDo not deactivate ESP®.
In rare cases (
Ypage 71), it may be best to deactivate ESP®.
Observe the important safety notes on ESP®(Ypage 70).
åN The yellow ESP®OFF warning lamp is lit while the engine is running.
ESP®is deactivated.
GWARNING
If ESP
®is switched off, ESP®is unable to stabilize the vehicle.
Further driving systems or driving safety systems are thus restricted, e.g. Active
Blind Spot Assist. The system does not perform course-correcting brake applica-
tions.
There is an increased risk of skidding and an accident.
XReactivate ESP®.
In rare cases (
Ypage 71), it may be best to deactivate ESP®.
Observe the important safety notes on ESP®(Ypage 70).
XAdapt your driving style to suit the road and weather conditions.
If ESP
®cannot be activated:
XDrive on carefully.
XContact a qualified specialist workshop and have ESP®checked.
Warning and indicator lamps in the instrument cluster285
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
÷åNThe yellow ESP®and ESP®OFF warning lamps are lit while the engine is running.
ESP®, BAS, Active Brake Assist, Active Brake Assist with cross-traffic function,
ESP®trailer stabilization, PRE‑SAFE®, PRE‑SAFE®PLUS, the HOLD function, hill
start assist, Crosswind Assist, STEER CONTROL, Active Lane Keeping Assist and
Active Blind Spot Assist are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
GWARNING
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 stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
÷åN The yellow ESP®and ESP®OFF warning lamps are lit while the engine is running.
ESP®, BAS, Active Brake Assist, Active Brake Assist with cross-traffic function,
ESP®trailer stabilization, PRE‑SAFE®, PRE‑SAFE®PLUS, the HOLD function, hill
start assist, Crosswind Assist, STEER CONTROL, Active Lane Keeping Assist and
Active Blind Spot Assist are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete
GWARNING
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 stabilize the vehicle.
There is an increased risk of skidding and an accident.
XCarefully drive a suitable distance, making slight steering movements at a speed
above 12 mph (20 km/h).
The functions mentioned above are available again when the warning lamp goes
out.
If the warning lamp is still on:
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
286Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
F!NF (USA only), !(Canada only): the red indicator lamp for the electric
parking brake flashes or is lit and/or the yellow warning lamp for the electric
parking brake is lit.
XObserve the additional display messages in the multifunction display.
6N The red restraint system warning lamp is lit while the engine is running.
The restraint system is malfunctioning.
GWARNING
The air bags or Emergency Tensioning Devices may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XContact a qualified specialist workshop and have the restraint system checked.
For further information about the restraint system, see (
Ypage 44).
Warning and indicator lamps in the instrument cluster287
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 (for vehicles with gasoline engines)
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.
Vehicles with a diesel engine: the fuel tank has been run dry (
Ypage 158).
XStart the engine three to four times after refueling.
If the yellow Check Engine warning lamp goes out, emergency running mode is
canceled. The vehicle need not be checked.
In 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 require-
ments 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 gauge is at the start of the scale.
The temperature sensor for the coolant temperature gauge is malfunctioning.
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 161).
XConsult a qualified specialist workshop.
288Warning and indicator lamps in the instrument cluster
On-board computer and displays