Page 377 of 497

Display messages
Possible causes/consequences and
M
MSolutions Ð
Power Power
steering
steering mal‐
mal‐
function See Own‐
function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident. X Check whether you are able to apply the extra force required.
If you are able to steer safely: X Drive on carefully.
X Consult a qualified specialist workshop immediately.
If you are unable to steer safely:
X Do not drive on.
X Consult a qualified specialist workshop. Telephone No ser‐ Telephone No ser‐
vice vice 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. ¥
Top Top
up
upwasher
washer fluid
fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Top up the washer fluid (Y page 418).Key
Display messages
Possible causes/consequences and
M MSolutions Â
Key does not Key does not
belong to vehicle belong to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Consult a qualified specialist workshop. Â
Change key batter‐ Change key batter‐
ies ies The key battery is discharged.
X Replace the batteries (Y page 98).374
Display
messagesOn-board computer and displays
Page 378 of 497

Display messages
Possible causes/consequences and
M
MSolutions Â
Key not detected Key not detected
(white display mes-
sage) The key is currently undetected.
X Change the location of the key in the vehicle.
If the key still cannot be detected: X Insert the key into the ignition lock and turn it to the desired
position. Â
Key not detected Key not detected
(red display message) The key 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 to prevent it from rolling away (Y page 219).
X Locate the key.
X Press aon 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 to prevent it from rolling away (Y page 219).
X Insert the key into the ignition lock and bring into key mode. Â
Remove starting Remove starting
button, then button, then
insert key insert key The key is continually undetected.
The key detection function has a temporary malfunction or is
faulty. A warning tone also sounds.
X Insert the key into the ignition lock and turn it to the desired
position.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
General notes
Some systems carry out a self-diagnosis when the ignition is switched on. Several warning and indicator lamps can thereby temporarily light up or flash. This behaviour is non-critical. These
warning and indicator lamps only indicate a malfunction if they light up or flash after the engine is started or during a journey. Wa
rning and indi cator lamps in the instrument cluster
375On-board computer and displays Z
Page 379 of 497

Safety
Seat belts Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ü
N
Only for certain countries: the red seat belt warning lamp lights up for
6 seconds after the engine starts.
The seat belt warning lamp reminds the driver and front passenger to fasten
their seat belts.
X Fasten your seat belt (Y page 50).ü
N
Only for certain countries: the red seat belt warning lamp lights up after the
engine starts. In addition, a warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 50).
The warning tone ceases. ü
N
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 passenger has not fastened their seat belt.
X Fasten your seat belt (Y page 50).
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. ü
N
The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or passenger has not fastened their seat belt. At the same time, you are driving faster than 25 km/h or have briefly driven faster than 25 km/h.
X Fasten your seat belt (Y page 50).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. At the same time, you are
driving faster than 25 km/h or have briefly driven faster than 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. 376
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 380 of 497

Safety systems
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J
N
The yellow brake system warning lamp lights up while the engine is running
or the ECO start/stop function is activated.
PLUG-IN HYBRID vehicles: the yellow brake system warning lamp is shown in
the READY driving status.
G WARNING
The brake system is malfunctioning and the braking characteristics may be
affected.
There is a risk of an accident. X If the multifunction display shows a display message, please observe this.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. J
N
The red brake system warning lamp is lit while the engine is running.
PLUG-IN HYBRID vehicles: the red brake system warning lamp is shown in the READY driving status.
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 Safeguard the vehicle against rolling away (Y page 219).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. Warning and indicator lamps in the instrument cluster
377On-board computer and displays Z
Page 381 of 497
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J
N
The red brake system warning lamp is lit while the engine is running.
PLUG-IN HYBRID vehicles: the red brake system warning lamp is shown in the READY driving status.
A warning tone also sounds.
There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
Braking efficiency 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 Safeguard the vehicle against rolling away (Y page 219).
X Do not top up the brake fluid. Topping up will not rectify the fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 378
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 382 of 497

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions !
N
The yellow ABS warning lamp is lit while the engine is running.
PLUG-IN HYBRID vehicles: the yellow ABS warning lamp is shown in the READY
driving status.
ABS (Anti-lock Braking System) has been deactivated due to a fault. Therefore BAS (Brake Assist System), BAS PLUS with Cross-Traffic Assist, COLLISION
PREVENTION ASSIST PLUS, ESP ®
(Electronic Stability Program), PRE‑SAFE ®
,
PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake, the HOLD function, Hill Start Assist,
ESP ®
trailer stabilisation, Crosswind Assist, adaptive brake lights, STEER
CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist are also
deactivated.
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 may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Consult 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 be unavail- able. Warning and indicator lamps in the instrument cluster
379On-board computer and displays Z
Page 383 of 497

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions !
N
The yellow ABS warning lamp is lit while the engine is running.
PLUG-IN HYBRID vehicles: the yellow ABS warning lamp is shown in the READY
driving status.
A warning tone also sounds.
EBD is unavailable due to a malfunction. Therefore ABS, BAS, BAS PLUS with
Cross-Traffic Assist, COLLISION PREVENTION ASSIST PLUS, ESP ®
,
PRE‑ SAFE ®
, PRE‑SAFE ®
PLUS, PRE‑ SAFE®
Brake, the HOLD function, Hill Start
Assist, ESP ®
trailer stabilisation, Crosswind Assist, adaptive brake lights,
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, for example, if you
brake hard.
The steerability and braking characteristics may be severely affected. The
braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. 380
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 384 of 497

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J÷
!
N
The red brake system warning lamp and the yellow ESP ®
and ABS warning
lamps light up while the engine is running.
PLUG-IN HYBRID vehicles: the red brake warning lamp, yellow ESP ®
warning
lamp and ABS are shown in the READY driving status.
ABS and ESP ®
are unavailable due to a fault. 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, ESP ®
trailer stabilisation, Crosswind Assist, adaptive brake lights,
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, for example, if you
brake hard.
The steerability and braking characteristics may be severely affected. The
braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. ÷
N
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 Only depress the accelerator pedal as far as necessary when pulling away.
X Accelerate more gently 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 86) it may be better to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 85). Warning and indicator lamps in the instrument cluster
381On-board computer and displays Z