2015 MERCEDES-BENZ S-Class COUPE page 88

Display messages
Possible causes/consequences and
0050
0050Solutions 00AF
Key Not Detected Key Not Detected
(red display message) The SmartKey is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).
X Locate the SmartKey.
X Press 0076on the steering wheel to confirm the display mes-
sage. Because there is interference from a strong source of radio waves,
the key is not detected whilst the engine is running.
A warning tone also sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).
X Insert the SmartKey into the ignition lock and bring into key
mode. 00AF
Remove Remove
'Start'
'Start' But‐
But‐
ton and Insert Key
ton and Insert Key The SmartKey is continually undetected.
The SmartKey detection function has a temporary malfunction or
is faulty. A warning tone also sounds.
X Insert the SmartKey into the ignition lock and turn it to the
desired position.
X Visit a qualified specialist workshop. 278
Display
messagesOn-board computer and displays

Warning and indicator lamps in the instrument cluster
Safety
Seat belts Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00E9
0051
After 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.
X Fasten your seat belt (Y page 46).00E9
0051
After starting the engine, the red seat belt warning lamp lights up. In addi-
tion, a warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 46).
The warning tone ceases. 00E9
0051
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.
X Fasten your seat belt (Y page 46).
The warning lamp goes out.
There are objects on the front-passenger seat. X Remove the objects from the front-passenger seat and stow them in a
secure place.
The warning lamp goes out. 00E9
0051
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).
X Fasten your seat belt (Y page 46).
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).
X Remove 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. Warning and indicator lamps in the instrument cluster
279On-board computer and displays Z

Safety systems
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 0027004D
0051
0027 (USA only), 004D(Canada only): the red brake system warning lamp
is lit while the engine is running. A warning tone also sounds.
G WARNING
The brake boosting effect is malfunctioning and the braking characteristics
may be affected.
There is a risk of an accident.
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 circumstan-
ces.
X Secure the vehicle against rolling away (Y page 166).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 0027004D
0051
0027 (USA only), 004D(Canada only): the red brake system warning lamp
is lit while the engine is running. A warning tone also sounds.
There is not enough brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of an accident. 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 circumstan-
ces.
X Secure the vehicle against rolling away (Y page 166).
X Do not add brake fluid. Adding more will not remedy the malfunction.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 0027
0051
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
0026 symbol.
The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. 280
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 0027004D
00E50025
0051
0027 (USA only), 004D(Canada only): the red brake warning lamp, the
yellow ESP ®
warning lamp and the yellow ABS warning lamp are lit while the
engine is running.
ABS and ESP ®
are not available due to a malfunction. Therefore BAS, BAS
PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, EBD,
PRE‑SAFE ®
, PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake, the HOLD function, hill start
assist, Crosswind Assist, STEER CONTROL, Active Lane Keeping Assist and
Active Blind Spot Assist are also unavailable.
ATTENTION ASSIST is deactivated.
G WARNING
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 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.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop. 00E5
0051
The 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 DISTRONIC PLUS is deactivated.
X When pulling away, only depress the accelerator pedal as far as necessary.
X Ease off the accelerator pedal while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
In rare cases (Y page 72), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 71). Warning and indicator lamps in the instrument cluster
283On-board computer and displays Z

Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 00E5
0051
The yellow ESP ®
warning lamp is lit while the engine is running.
ESP ®
, BAS, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION
ASSIST PLUS, PRE ‑SAFE®
, PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake, the HOLD
function, hill start assist, Crosswind Assist, STEER CONTROL, Active Lane
Keeping Assist and Active Blind Spot Assist are unavailable due to a malfunc-
tion.
ATTENTION ASSIST is deactivated.
G WARNING
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.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop. 00BB
0051
The yellow ESP ®
OFF warning lamp is lit while the engine is running.
ESP ®
is deactivated.
G WARNING
If ESP ®
is switched off, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Reactivate ESP ®
.
In rare cases (Y page 72), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 71).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Have ESP ®
checked at a qualified specialist workshop. 284
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00490024
0051
0049 (USA only), 0024(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.
X Observe the additional display messages in the multifunction display. 0075
0051
The red restraint system warning lamp is lit while the engine is running.
The restraint system is faulty.
G WARNING
The air bags or Emergency Tensioning Devices may either be triggered unin-
tentionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Have the restraint system checked at a qualified specialist workshop imme-
diately.
For further information about the restraint system, see (Y page 42).Warning and indicator lamps in the instrument cluster
285On-board computer and displays Z

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00AC
0051
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the bar display.
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.
X Pull 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.
X Secure the vehicle against rolling away (Y page 166).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
287On-board computer and displays Z

Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 00AC
0051
The 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.
X Observe the additional display messages in the multifunction display.
X Pull over and stop the vehicle safely and switch off the engine, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).
X Leave the vehicle and keep a safe distance from the vehicle until the engine
has cooled down.
X Check the coolant level and add coolant, observing the warning notes
(Y page 322).
X If you need to add coolant more often than usual, have the engine coolant
system checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by
snow, slush or ice.
X Do not start the engine again until the coolant temperature is below 257 ‡
(125 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in mountainous
terrain, and stop-and-go traffic. 00AC
0051
The red coolant warning lamp comes on while the engine is running. A
warning tone also sounds.
The coolant temperature has exceeded 255 ‡ (124 †). The airflow to the
engine radiator may be blocked or the coolant level may be too low.
G WARNING
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.
X Observe the additional display messages in the multifunction display.
X Pull over and stop the vehicle safely and switch off the engine, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).288
Warning and indicator lamps in the instrument clusterOn-board computer and displays