2013 MERCEDES-BENZ CLA ESP inoperative

Important safety notes
If you fail to adapt your driving style or if you
are inattentive, the driving safety systems can
neither reduce the risk of accident nor over-
ride the laws of physics. Driving safety sys-
tems are merely aids designed to assist driv-
ing. You are responsible for the distance to
the vehicle in front, for vehicle speed and for
braking in good time. Always adapt your driv-
ing style to suit the prevailing road, weather
and traffic conditions and maintain a safe dis-
tance from the vehicle in front. Drive care-
fully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tyres and
the road surface. Pay particular attention
to the information regarding tyres, recom-
mended minimum tyre tread depths etc. in
the "Wheels and tyres" section
( Y page 316).
In wintry driving conditions, always use
winter tyres (M+S tyres) and, if necessary,
snow chains. Only in this way will the driv-
ing safety systems described in this section
work as effectively as possible.
ABS (Anti-lock Braking System)
General notes
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle when braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems
( Y page 64).
GWARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y page 256) and
display messages which may be shown in the
instrument cluster ( Y page 227).
ABS works from a speed of about
8 km/hupwards, regardless of road-surface
conditions. ABS works on slippery surfaces,
even when you only brake gently.
Braking
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.XTo make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving.
BAS (Brake Assist)
General notes
BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
64Driving safety systemsSafety

Safety systemsDisplay messagesPossible causes/consequences and M Solutions!÷
currently unavail‐
able See Owner's
ManualABS (Anti-lock Braking System), ESP ®
(Electronic Stability Pro-
gram), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function, hill
start assist and ESP ®
trailer stabilisation are temporarily unavail-
able.
The adaptive brake lights and COLLISION PREVENTION ASSIST/
COLLISION PREVENTION ASSIST PLUS may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.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.
XCarefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.!÷
inoperative See
Owner's ManualABS, ESP ®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist
and ESP ®
trailer stabilisation are unavailable due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST/
COLLISION PREVENTION ASSIST PLUS may also have failed.
In addition, the J, ÷ , å and ! warning lamps light
up in the instrument cluster.
ATTENTION ASSIST is deactivated.GWARNINGDisplay messages227On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions÷
inoperative See
Owner's ManualESP ®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are not available due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST/
COLLISION PREVENTION ASSIST PLUS may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
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.
XDrive on carefully.XVisit a qualified specialist workshop.T !
÷
inoperative See
Owner's ManualEBD (electronic brake force distribution), ABS, ESP ®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer stabi-
lisation are unavailable due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST/
COLLISION PREVENTION ASSIST PLUS may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
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.
XDrive on carefully.XVisit a qualified specialist workshop immediately.Display messages229On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsJ
Check brake fluid
levelThere is insufficient brake fluid in the brake fluid reservoir.
In addition, the red J warning lamp lights up in the instrument
cluster and a warning tone sounds.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).XConsult a qualified specialist workshop.XDo not top up the brake fluid. This does not correct the fault.#
Check brake pad
wearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.PRE-SAFE
inoperative See
Owner's ManualImportant functions of PRE-SAFE ®
have failed. All other occupant
safety systems, e.g. airbags, remain available.XVisit a qualified specialist workshop immediately.Collision Preven‐
tion Assist Plus
currently unavail‐
able See Owner's
ManualCOLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
R the radar sensor cover in the radiator trim is dirty.
R the function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
Once the causes listed above no longer apply, the display message
goes out.
COLLISION PREVENTION ASSIST PLUS is operational again.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 162).XClean the radar sensor cover in the radiator grille
( Y page 291).XRestart the engine.Display messages233On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsCollision Preven‐
tion Assist Plus
inoperativeCOLLISION PREVENTION ASSIST PLUS is malfunctioning. The dis-
tance warning signal may also have failed.XVisit a qualified specialist workshop.PRE-SAFE
Function currently
limited See Own‐
er's ManualAdaptive Brake Assist is temporarily inoperative. Possible causes:
R the front bumper is dirty.
R the function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
Once the causes listed above no longer apply, the display message
goes out.
Adaptive Brake Assist is operational again.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 162).XClean the front bumper ( Y page 291).XRestart the engine.PRE-SAFE
Function limited
See Owner's ManualAdaptive Brake Assist is faulty. The distance warning signal may
also have failed.XVisit a qualified specialist workshop.üIf the symbol appears in the multifunction display, a seat belt
tongue has been inserted into a rear seat belt buckle.
Further information on the status indicator for the rear seat belts
( Y page 49).234Display 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

Display messagesPossible causes/consequences and M SolutionsAdaptive Main-beam
Assist inoperativeAdaptive Highbeam Assist is faulty.XVisit a qualified specialist workshop.Adaptive Main-beam
Assist currently
unavailable See
Owner's ManualAdaptive Highbeam Assist is deactivated and temporarily inoper-
ative. Possible causes:
R the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.XClean the windscreen.
If the system detects that the camera is fully operational again,
the Adaptive Main-beam Assist available again message
is displayed.
Adaptive Highbeam Assist is operational again.
Engine
Display messagesPossible causes/consequences and M Solutions+
Top up coolant See
Owner's ManualThe coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.XTop up the coolant, observing the warning notes before doing
so ( Y page 285).XIf the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop.?The fan motor is faulty.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.240Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutions4
Check eng. oil
lev. when next
refuellingThe engine oil level has dropped to the minimum level.
A warning tone also sounds.XCheck the oil level when next refuelling, at the latest
( Y page 284).XIf necessary, top up the engine oil ( Y page 285).XHave the engine checked at a qualified specialist workshop if
the engine oil needs topping up more often than usual.æ
Reserve fuel levelThe fuel level has dropped into the reserve range.
The auxiliary heating cannot be operated.XRefuel at the nearest filling station.çThere is very little fuel in the fuel tank.
The auxiliary heating cannot be operated.XRefuel at the nearest filling station without fail.¸
Replace air
cleaner elementVehicles with a diesel engine: the engine air filter is dirty and must
be replaced.XVisit a qualified specialist workshop.!
Clean fuel filterVehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.XVisit a qualified specialist workshop.
Driving systems
Display messagesPossible causes/consequences and M SolutionsÀ
Attention Assist
Drowsiness detec‐
tedBased on certain criteria, ATTENTION ASSIST has detected fatigue
or a lack of concentration on the part of the driver. A warning tone
also sounds.XIf necessary, take a break.
During long journeys, take regular breaks in good time so that you
get enough rest.
À
Attention Assist
inoperativeATTENTION ASSIST is inoperative.XVisit a qualified specialist workshop.242Display messagesOn-board computer and displays