Page 281 of 398

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 0025
0051
The 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 00E5and00BB warning lamps may light up in the instrument
cluster.
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 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.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. 0027004D
00E500BB
0025
0051
0027 (USA only), 004D(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.
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 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.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. Warning and indicator lamps in the instrument cluster
279On-board computer and displays Z
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Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 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 Active Distance Assist DISTRONIC 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 71), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 70). 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.
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.
X Reactivate ESP ®
.
In rare cases (Y page 71), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 70).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Contact a qualified specialist workshop and have ESP ®
checked. 280
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 283 of 398

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00E500BB
0051
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.
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 immediately. 00E500BB
0051
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
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 Carefully 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: X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. Warning and indicator lamps in the instrument cluster
281On-board computer and displays Z
Page 284 of 398

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 malfunctioning.
G WARNING
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.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Contact a qualified specialist workshop and have the restraint system checked.
For further information about the restraint system, see (Y page 44).282
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Page 285 of 398

Engine
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00B9
0051
The yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with gasoline engines)
R in the fuel system
The emission limit values may be exceeded and the engine may be in emergency mode.
X Visit a qualified specialist workshop immediately.
Vehicles with a diesel engine: the fuel tank has been run dry (Y page 153).
X Start 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. 00B6
0051
The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. 00B6
0051
The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the 00B9Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler cap.
X If the fuel filler cap is closed: visit a qualified specialist workshop.00AC
0051
The 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.
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 156).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
283On-board computer and displays Z
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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 defective.
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 156).
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 324).
X If you have to add coolant frequently, have the engine cooling 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 248 ‡
(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, 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.
The coolant temperature has exceeded 248 ‡ (120 †). 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 156).
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 324).
X If you have to add coolant frequently, have the engine cooling system checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice. 284
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 287 of 398

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions X
At coolant temperatures below 248 ‡ (120 †), drive to the nearest qualified
specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic. Driving systems
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00BA
0051
The red distance warning lamp lights up while the vehicle is in motion. A warning
tone also sounds.
You are approaching a vehicle, a pedestrian or a stationary obstacle in your line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to brake or take
evasive action.
Further information about Active Distance Assist DISTRONIC (Y page 171).
Further information on the distance warning function of Active Brake Assist
(Y page 67).
Further information on the distance warning function of Active Brake Assist with
cross-traffic function (Y page 72). Warning and indicator lamps in the instrument cluster
285On-board computer and displays Z
Page 288 of 398

Tires
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 0077
0051
The yellow tire pressure monitor warning lamp (pressure loss/malfunction) is lit.
The tire pressure monitor has detected a loss of pressure in at least one of the tires.
G WARNING
Tire pressures that are too low pose the following hazards: R they may burst, especially as the load and vehicle speed increase.
R they may wear excessively and/or unevenly, which may greatly impair tire trac-
tion.
R the driving characteristics, as well as steering and braking, may be greatly
impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking maneuvers. Pay
attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 156).
X Observe the additional display messages in the multifunction display.
X Check the tires and, if necessary, follow the instructions for a flat tire
(Y page 335).
X Check the tire pressure (Y page 358).
X If necessary, correct the tire pressure. 0077
0051
The yellow tire pressure monitor warning lamp (pressure loss/malfunction)
flashes for approximately one minute and then remains lit.
The tire pressure monitor is faulty.
G WARNING
The system is possibly unable to recognize or register low tire pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction display.
X Visit a qualified specialist workshop immediately. 286
Warning and indicator lamps in the instrument clusterOn-board computer and displays