warning lights MERCEDES-BENZ CLA 2013 Service Manual

Display messagesPossible causes/consequences and M Solutions6
Rear left-hand
side malfunction
Consult workshop  
or  Rear right-hand
side malfunction
Consult workshopSRS has malfunctioned at the rear on the left or right. The 6
warning lamp also lights up in the instrument cluster.GWARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
XVisit a qualified specialist workshop.6
Left windowbag mal‐
function Consult
workshop  or Right
windowbag malfunc‐
tion Consult work‐
shopThere is a malfunction in the left-hand and/or right-hand window-
bag. The 6 warning lamp also lights up in the instrument clus-
ter.GWARNING
The left or right windowbag may either be triggered unintentionally
or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
XVisit a qualified specialist workshop.
Lights
i Display messages about LEDs:
This display message will only appear if all the LEDs have failed.
Display messagesPossible causes/consequences and M Solutionsb
Left cornering
light  or Right cor‐
nering lightThe left or right-hand cornering light is faulty.XCheck whether you are permitted to replace the bulb yourself
( Y page 114).
or
XVisit a qualified specialist workshop.b
Left dipped beam  
or  Right dipped
beamThe left or right-hand dipped-beam headlamp is faulty.XCheck whether you are permitted to replace the bulb yourself
( Y page 114).
or
XVisit a qualified specialist workshop.236Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutionsb
Reversing lightThe reversing lamp is faulty.XCheck whether you are permitted to replace the bulb yourself
( Y page 114).
or
XVisit a qualified specialist workshop.b
Left tail lamp  or 
Right tail lamp The left or right-hand tail lamp is faulty.XCheck whether you are permitted to replace the bulb yourself
( Y page 114).
or
XVisit a qualified specialist workshop.b
Left daytime driv‐
ing lamp  or Right
daytime driving
lampThe left-hand or right-hand daytime driving lamp is faulty.XCheck whether you are permitted to replace the bulb yourself
( Y page 114).
or
XVisit a qualified specialist workshop.b
Intell. Light Sys‐
tem inoperativeThe Intelligent Light System is faulty. The lights remain available
without the Intelligent Light System.XVisit a qualified specialist workshop.b
Malfunction See
Owner's ManualThe exterior lighting is faulty.XVisit a qualified specialist workshop.Vehicles with trailer tow hitch: a fuse may have blown.XCheck the fuses ( Y page 312).XIf necessary, replace the blown fuse. Observe the warning notes
as you do so.
If the display message continues to be displayed:
XVisit a qualified specialist workshop.b
AUTO lights inoper‐
ativeThe light sensor is faulty.XVisit a qualified specialist workshop.b
Switch off lightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to Ã.Display messages239On-board computer and displaysZ

Warning and indicator lamps in the instrument cluster
Seat belts
ProblemPossible causes/consequences and M Solutionsü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
for six seconds after
the engine starts.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 46).ü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
after the engine starts.
In addition, a warning
tone sounds for up to
six seconds.The driver's seat belt is not fastened.XFasten your seat belt ( Y page 46).
The warning tone ceases.ü
The red seat belt warn-
ing 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.XFasten your seat belt ( Y page 46).
The warning lamp goes out.There are objects on the front-passenger seat.XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out.ü
The red seat belt warn-
ing lamp flashes and an
intermittent audible
warning sounds.The driver or front 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.XFasten your seat belt ( Y page 46).
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.XRemove 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 cluster255On-board computer and displaysZ

Safety systemsProblemPossible causes/consequences and M SolutionsJ
The red brake system
warning lamp is lit while
the engine is running. A
warning tone also
sounds.There is insufficient brake fluid in the brake fluid reservoir.GWARNING
The braking efficiency may be impaired.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XSecure the vehicle against rolling away ( Y page 162).XDo not top up the brake fluid. Topping up will not rectify the
fault.XConsult a qualified specialist workshop.XObserve the additional display messages in the multifunction
display.!
The yellow ABS warning
lamp is lit while the
engine is running.ABS (Anti-lock Brake System) has been deactivated due to a fault.
Therefore, BAS (Brake Assist), COLLISION PREVENTION ASSIST,
COLLISION PREVENTION ASSIST PLUS, ESP ®
(Electronic Stability
Program), PRE-SAFE ®
, the HOLD function, hill start assist, the
adaptive brake lights and ESP ®
trailer stabilisation, for example,
are also deactivated.
ATTENTION ASSIST is deactivated.GWARNING
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 affec-
ted. 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.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit 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 trans-
mission, will be unavailable.
256Warning and indicator lamps in the instrument clusterOn-board computer and displays

ProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running.ABS is temporarily unavailable. Therefore, BAS, COLLISION PRE-
VENTION ASSIST, COLLISION PREVENTION ASSIST PLUS, ESP ®
,
EBD (electronic brake force distribution), PRE-SAFE ®
, the HOLD
function, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation, for example, are also deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.GWARNING
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 affec-
ted. The braking distance may increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is a risk of an accident.
XCarefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.Warning and indicator lamps in the instrument cluster257On-board computer and displaysZ

ProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds.EBD is faulty. Therefore, ABS, BAS, COLLISION PREVENTION
ASSIST, COLLISION PREVENTION ASSIST PLUS, ESP ®
,
PRE-SAFE ®
, the HOLD function, hill start assist, the adaptive brake
lights and ESP ®
trailer stabilisation, for example, are not available
either.
ATTENTION ASSIST is deactivated.GWARNING
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 affec-
ted. 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.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.J ֌!
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, COLLISION
PREVENTION ASSIST, COLLISION PREVENTION ASSIST PLUS,
EBD, PRE-SAFE ®
, the HOLD function, hill start assist; the adaptive
brake lights and ESP ®
trailer stabilisation, for example, are not
available either.
ATTENTION ASSIST is deactivated.GWARNING
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 affec-
ted. 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.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.258Warning and indicator lamps in the instrument clusterOn-board computer and displays

ProblemPossible causes/consequences and M Solutions÷
The yellow ESP ®
warn-
ing 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.XOnly depress the accelerator pedal as far as necessary when
pulling away.XAccelerate more gently while the vehicle is in motion.XAdapt your driving style to suit the road and weather conditions.XDo not deactivate ESP ®
.
For exceptions, see: ( Y page 68).å
The yellow ESP ®
OFF
warning lamp is lit while
the engine is running.ESP ®
and ESP ®
trailer stabilisation are deactivated. ESP ®
will not
stabilise the vehicle if it starts to skid or if a wheel starts to spin.GWARNING
If ESP ®
is switched off, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
XReactivate ESP ®
.
For exceptions, see: ( Y page 68).XAdapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
XHave ESP ®
checked at a qualified specialist workshop.֌
The yellow ESP ®
and
ESP ®
OFF warning
lamps are lit while the
engine is running.ESP ®
, BAS, COLLISION PREVENTION ASSIST, COLLISION PRE-
VENTION ASSIST PLUS, PRE-SAFE ®
, the HOLD function, hill start
assist, the adaptive brake lights and ESP ®
trailer stabilisation are
not available due to a malfunction.
ATTENTION ASSIST is deactivated.GWARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance may thus 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.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.Warning and indicator lamps in the instrument cluster259On-board computer and displaysZ

ProblemPossible causes/consequences and M Solutions֌
The yellow ESP ®
and
ESP ®
OFF warning
lamps are lit while the
engine is running.ESP ®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are temporarily unavailable.
The adaptive brake lights and COLLISION PREVENTION ASSIST/
COLLISION PREVENTION ASSIST PLUS may also have failed.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete.GWARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance may thus 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.
XCarefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.260Warning and indicator lamps in the instrument clusterOn-board computer and displays

EngineProblemPossible causes/consequences and M Solutions;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.There may be a fault, 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 petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.Vehicles with a diesel engine: the fuel tank has been run dry
( Y page 161).XStart the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need not be
checked.æ
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.XRefuel at the nearest filling station.?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
start of the scale.The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.XStop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.XSecure the vehicle against rolling away ( Y page 162).XConsult a qualified specialist workshop.262Warning and indicator lamps in the instrument clusterOn-board computer and displays

ProblemPossible causes/consequences and M SolutionsXLeave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.XCheck the coolant level and top up the coolant ( Y page 285).
Observe the warning notes as you do so.XIf you have to top up the coolant frequently, have the engine
cooling system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.XIf the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.XAvoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic.
Driving systems
ProblemPossible causes/consequences and M Solutions·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.The distance to the vehicle in front is too small for the speed
selected.XIncrease the distance.·
The red distance warn-
ing 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.XBe prepared to brake immediately.XPay careful attention to the traffic situation. You may have to
brake or take evasive action.
For further information about the distance warning function of
COLLISION PREVENTION ASSIST ( Y page 65).
For further information about COLLISION PREVENTION ASSIST
PLUS ( Y page 67).
264Warning and indicator lamps in the instrument clusterOn-board computer and displays