Display messages Possible causes/consequences and
M SolutionsIf these conditions are fulfilled, the front-passenger seat can be
occupied
again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see ( Y page 46). Front Passenger
Airbag Disabled
See Operator's
Manual The front-passenger air bag is disabled during the journey, even
though:
R
an adult
or
R a person larger than a certain size is occupying the front-
passenger seat.
If additional forces are applied to the seat, the system may
interpret the occupant's weight as lower than it actually is.
G WARNING
The front-passenger air bag does not deploy during an accident.
There is an increased risk of injury.
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 167).
X Switch the ignition off.
X Have the occupant get out of the vehicle.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the 45
indicator lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45
indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS has deactivated the front-
passenger air bag ( Y page 46).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not be shown in
the multifunction display.
X Wait for a period of at least 60 seconds until the necessary
system checks have been completed.
X Make sure that the display messages do not appear in the
multifunction display. Display messages
235
On-board computer and displays Z
Display messages Possible causes/consequences and
M SolutionsIf these conditions are fulfilled, the front-passenger seat can be
occupied
again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see ( Y page 46). Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed. Display messages Possible causes/consequences and
M Solutionsb
Check Left
Cornering Light
or
Check Right
Cornering light The left or right-hand cornering light is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check Left Low
Beam or Check
Right Low Beam The left or right-hand low-beam headlamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Turn Signal or
Check Rear Right
Turn Signal The rear left-hand or rear right-hand turn signal is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check Front Left
Turn Signal or
Check Front Right
Turn Signal The front left-hand or front right-hand turn signal is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop.236
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M Solutionsb
Rear Fog Lamp The rear fog lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check Front Left
Parking Lamp or
Check Front Right
Parking Lamp The front left or front right parking or standing lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check
Left Reverse
Lamp or Check
Right Reverse Lamp The left or right-hand backup lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Check Front Left
Sidemarker Lamp
or
Check Front Right
Sidemarker Lamp The left or right front side marker lamp is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 129).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Sidemarker Lamp
or
Check Rear Right
Sidemarker Lamp The rear left or right side marker lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 129).
or
X Visit a qualified specialist workshop. b
Check
Left Daytime
Running Light or
Check Right
Daytime Running
Light The left-hand or right-hand daytime running lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 130).
or
X Visit a qualified specialist workshop. b
Active Headlamps
Inoperative The active light function is defective.
X
Visit a qualified specialist workshop.238
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M Solutionsb
Malfunction See
Operator's Manual The exterior lighting is defective.
X
Visit a qualified specialist workshop. b
Auto
Lamp Function
Inoperative The light sensor is defective.
X
Visit a qualified specialist workshop. b
Switch Off Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã.Adaptive Highbeam
Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Highbeam
Assist Currently
Unavailable See
Operator's Manual Adaptive Highbeam Assist is deactivated and temporarily
inoperative. Possible causes are:
R
the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
X Clean the windshield.
If the system detects that the camera is fully operational again,
the Adaptive Highbeam Assist Now Available message is
displayed.
Adaptive Highbeam Assist is operational again. Display messages
239
On-board computer and displays Z
Display messages Possible causes/consequences and
M SolutionsBlind Spot Assist
Currently
Unavailable See
Operator's Manual
or Active Blind
Spot Assist
Currently
Unavailable See
Operator's Manual Blind Spot Assist or Active Blind Spot Assist is temporarily
inoperative. Possible causes are:
R
the sensors are dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
When the causes stated above no longer apply, the display
message disappears.
Blind Spot Assist or Active Blind Spot Assist is operational again.
If the display message does not disappear:
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 167).
X Clean the sensors ( Y page 304).
X Restart the engine. Blind Spot Assist
Inoperative or
Active Blind Spot
Assist Inoperative Blind Spot Assist or Active Blind Spot Assist is defective.
The yellow
9 indicator lamps also light up in the exterior
mirrors.
X Visit a qualified specialist workshop. Parking Guidance
Inoperative Parking Guidance is malfunctioning (
Y page 194).
X Restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop.244
Display messagesOn-board computer and displays
Safety
Seat belts Problem Possible causes/consequences and
M Solutionsü
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 55).ü
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 55).
The warning tone ceases. ü
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 55).
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
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 55).
The warning lamp goes out and the intermittent warning 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 intermittent warning tone
ceases. Warning and indicator lamps in the instrument cluster
257
On-board computer and displays Z
Engine
Problem Possible causes/consequences and
M Solutions;
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
R in the fuel system
The emission limit values may be exceeded and the engine may
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 Check Engine 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. 8
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. 8
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the ;
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. ?
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 167).
X Consult a qualified specialist workshop.262
Warning and indicator lamps in the instrument cluster
On-board computer and displays
Problem Possible causes/consequences and
M SolutionsX
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 296).
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
M Solutions·
The red distance
warning lamp lights up
while the vehicle is in
motion.
A warning tone
also sounds. You are approaching a vehicle 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 on DISTRONIC PLUS ( Y page 177).
Further information on PRE-SAFE ®
Brake (Y page 67). 264
Warning and indicator lamps in the instrument cluster
On-board computer and displays