
Display messages Possible causes/consequences and
0001 Solutions
0001
Power Steering
Malfunction See
Operator's Manual The powe
rsteering is malfunctioning.
Aw arning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a ris kofanaccident.
X Check whethe ryou are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. Phone No Service Your vehicle is outside the network provider's transmitter/
receiver range.
X
Wait until the mobile phone operational readiness symbol
appears in the multifunction display. 001E
Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X
Add washer fluid (Y page 368).Wiper
Malfunctioning The windshield wipers are malfunctioning.
X
Visit a qualified specialist workshop. Hazard Warning
Flashers
Malfunctioning The hazard warning lamps are faulty.
X
Visit a qualified specialist workshop. SmartKey
Display messages Possible causes/consequences and
0001 Solutions
0002
Key Does Not
Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. 0002
Take
Your Key from
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. 0002
Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. 314
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
0001 Solutions
0002
Replace
Key Battery The batteries of the KEYLESS-GO key are discharged.
X Change the batteries ( Ypage 81). 0002
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. 0002
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. 0002
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. 0002
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

Display messages Possible causes/consequences and
0001 Solutions
0002
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. 0002
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)
0012 (USA) Brakes (Y page 318)
0009 (Canada)B rakes (Ypage 318)
0019 ABS (Ypage 319)
000F ESP®
(Y page 321)
0017 ESP®
OFF (Y page 321)
0008 (USA) Electric parking brake (red)
(Ypage 324)
000D (Canada )Electric parking brake (red)
(Y page 324)
000D 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)
000F Distance warning function
(Ypage 328) 0010
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

Problem Possible causes/consequences and
0001 Solutions
0019
The yellow ABS warning
lamp is lit while the
engine is running.
ABS (Anti-lock Braking System) is deactivated due to a
malfunction. For this reason, BAS (Brake Assist), BAS PLUS,
ESP
®
(Electronic Stability Program), PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST, the HOLD function, hill
start assist and ESP ®
trailer stabilization are also deactivated, for
example.
ATTENTION ASSIST is deactivated.
G WARNING
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
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. Warning and indicator lamps in the instrument cluster
319On-board computer and displays Z

Problem Possible causes/consequences and
0001 Solutions
0019
The yellow ABS warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. Therefore, BAS, BAS PLUS, ESP
®
,
EBD (electronic brake force distribution), PRE-SAFE ®
,
PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST, the HOLD
function, hill start assist, and ESP ®
trailer stabilization, for
example, are also deactivated.
ATTENTION ASSIST is deactivated.
Possible causes are:
R Self-diagnosis is not yet complete.
R The on-board voltage may be insufficient.
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 a risk of an accident.
X Carefully drive a short distance on a suitable stretch of road,
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. 320
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
0001 Solutions
0019
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds. EBD is malfunctioning. Therefore, ABS, BAS, BAS PLUS, ESP
®
,
PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST,
the HOLD function, hill start assist and ESP ®
trailer stabilization,
for example, are not available either.
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. 0012
(USA only)
0009 (Canada only)
000F00170019
The red brake warning
lamp, the yellow ESP ®
and ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. ABS and ESP
®
are malfunctioning. Therefore, BAS, BAS PLUS,
PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST,
the HOLD function, hill start assist and ESP ®
trailer stabilization,
for example, are also not available.
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. Warning and indicator lamps in the instrument cluster
321On-board computer and displays Z

Problem Possible causes/consequences and
0001 Solutions
000E
The red coolant
warning lamp comes on
while the engine is
running. 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.
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 179).
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 367).
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
under 248 ‡(120 †). 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. 000E
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.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive whe nyour 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. Warning and indicator lamps in the instrument cluster
327On-board computer and displays Z

Problem Possible causes/consequences and
0001 Solutions
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 179).
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 367).
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 At coolant temperatures under 248 ‡(120 †), drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. Driving systems
Problem Possible causes/consequences and
0001 Solutions
000F
The red distance
warning function
warning lamp comes on
while the vehicle is
moving. A warning tone
also sounds.
You are approaching a vehicle or a stationary obstacle in you
rline
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 on DISTRONIC PLUS (Y page 194).
Further information on PRE-SAFE ®
Brake (Y page 73).
Further information on the distance warning function
(Y page 68). 328
Warning and indicator lamps in the instrument clusterOn-board computer and displays