Page 317 of 462

Display messages Possible causes/consequences and
0001 Solutions
0001
Replace
Key Battery The batteries of the KEYLESS-GO key are discharged.
X Change the batteries ( Ypage 83). 0001
Don't Forget Your
Key This display message is displayed fo
ramaximum of 60 seconds
and is simply a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X Remember to take the KEYLESS-GO key with you when you
leave the vehicle. 0001
Key Not Detected
(red display message) The KEYLESS-GO key is not in the vehicle.
Aw
arning tone also sounds.
If the engine is switched off, you can no longer loc kthe 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 179).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
Aw
arning tone also sounds.
X Pull ove rand stop the vehicle safely as soo nas possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 179).
X Operate the vehicle with the SmartKey in the ignition lock. 0001
Key Not Detected
(white display
message) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the SmartKey with the KEYLESS-GO
functions in the vehicle.
If the KEYLESS-GO key is still not detected:
X Operate the vehicle with the SmartKey in the ignition lock. 0001
Key Detected in
Vehicle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. Display messages
315On-board computer and displays Z
Page 318 of 462

Display messages Possible causes/consequences and
0001 Solutions
0001
Remove 'Start'
Button and Insert
Key KEYLESS-GO is temporarily malfunctioning or is defective. 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. 0001
Close Doors to
Lock Vehicle At leas
tone door is open. Awarning tone also sounds.
X Close all doors and loc kthe vehicle again. Warning and indicator lamps in the
instrument cluster
Overview
000D Low-beam headlamps
(Ypage 121)
0016 Parking lamps (Y page 122)
000C High-beam headlamps
(Ypage 124)
00070006 Turn signal (Ypage 123)
0014 Seat belts (Ypage 317)
0011 (USA) Brakes (Y page 318)
0008 (Canada)B rakes (Ypage 318)
0019 ABS (Ypage 319)
000F ESP®
(Y page 321)
0017 ESP®
OFF (Y page 321)
0007 (USA) Electric parking brake (red)
(Ypage 324)
000C (Canada )Electric parking brake (red)
(Y page 324)
000C Electric parking brake
(yellow) (Y page 324)
001F SRS (Ypage 324)
0010 Check Engine (Y page 325)
0012 Reserve fuel (Ypage 325)
000E Coolant (Ypage 326)
000E Distance warning function
(Ypage 328) 000F
Diesel engine: preglow
(Y page 159)
0012 Tire pressure monitor
(Ypage 329) 316
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 319 of 462

Safety
Seat belts Problem Possible causes/consequences and
0001 Solutions
0014
After starting the
engine, the red seat
belt warning lamp lights
up for
6seconds. The seat belt warning lamp reminds the driver and fron
tpassenger
to fasten their seat belts.
X Faste nyour seat belt (Y page 57). 0014
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to six seconds.
The driver's seat belt is not fastened.
X
Fasten your seat belt (Y page 57).
The warning tone ceases. 0014
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 57).
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. 0014
The red seat belt
warning lamp flashes
and an intermittent
audible warning
sounds.
The driver or front passenger has not fastened their seat belt. You
are driving faster than 15 mph (25 km/h) or have briefly driven
faster than 15 mph (25 km/h).
X
Fasten your seat belt (Y page 57).
The warning lamp goes out and the intermittentw arning tone
ceases. There are objects on the front-passenger seat
.You are driving
faster than 15 mph (25 km/h) or have briefly 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 intermittentw arning tone
ceases. Warning and indicator lamps in the instrument cluster
317On-board computer and displays Z
Page 320 of 462

Safety systems
Problem Possible causes/consequences and
0001 Solutions
0011
(USA only)
0008 (Canada only)
The red brake system
warning lamp comes on
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 circumstances.
X Secure the vehicle against rolling away (Y page 179).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 0011
(USA only)
0008 (Canada only)
The red brake system
warning lamp comes on
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 circumstances.
X Secure the vehicle against rolling away (Y page 179).
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. 318
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 324 of 462

Problem Possible causes/consequences and
0001 Solutions
000F
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 ®
. 0017
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 ®
.
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. 000F0017
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
,B AS, BAS PLUS, PRE-SAFE ®
,P RE-SAFE ®
Brake ,COLLISION
PREVENTION ASSIST, the HOLD function, hill start assist and
ESP ®
trailer stabilization 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. 322
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 326 of 462
Problem Possible causes/consequences and
0001 Solutions
0007
(USA only)
000C (Canada only)
The red electric parking
brake indicator lamp
flashes or lights up
and/or
000C
warning lamp for the
electric parking brake
lights up. X
Observe the additional display messages in the multifunction
display. 001F
The red SRS warning
lamp is lit while the
engine is running.
There is a malfunction in the SRS (Supplemental Restraint
System).
G WARNING
The air bags or Emergency Tensioning Devices may either be
triggered unintentionally or, in the event of an accident, may not
be triggered.
There is an increased risk of injury.
X Drive on carefully.
X Have SRS checked at a qualified specialist workshop
immediately.
For further information about SRS, see (Y page 43).324
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 327 of 462

Engine
Problem Possible causes/consequences and
0001 Solutions
0010
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 a gasoline engine)
R in the fuel system
The emission limit values may be exceeded and the engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified
specialist workshop as soon as the yellow Chec kEngine 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. Vehicles with a diesel engine: the fuel tank has been run dry
(Y
page 176).
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. 0012
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. 0012
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the
0010
Check Engine warning
lamp may light up. The fuel system pressure is too low. 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. Warning and indicator lamps in the instrument cluster
325On-board computer and displays Z
Page 328 of 462
Problem Possible causes/consequences and
0001 Solutions
000E
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
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 179).
X Consult a qualified specialist workshop. 326
Warning and indicator lamps in the instrument clusterOn-board computer and displays