2014 MERCEDES-BENZ C-CLASS SALOON park assist

Display messages
Possible causes/consequences and
M
MSolutions T!
÷
inoperative See inoperative See
Owner's Manual Owner's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS,
PRE ‑SAFE ®
, HOLD function, hill start assist, ESP ®
trailer stabili-
sation, Crosswind Assist, adaptive brake lights, STEER CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist are
unavailable due to a malfunction.
BAS PLUS, PRE‑SAFE ®
Brake, PRE ‑SAFE®
PLUS and COLLISION
PREVENTION ASSIST PLUS may also have failed.
In addition, the ÷,åand! warning lamps light up in the
instrument cluster and a warning tone sounds.
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 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.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. J
Brake immediately Brake immediately A malfunction has occurred while the HOLD function is active.
or
With the HOLD function activated, you have:
R opened the driver's door and released the seat belt or
R switched off the engine
A tone may also sound at regular intervals. If you attempt to lock the vehicle, the tone becomes louder.
You cannot start the engine.
X Paying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message disap-
pears.
X Secure the vehicle against rolling away (Y page 207).
You can restart the engine. !
Release parking Release parking
brake brake The red
!indicator lamp flashes and a warning tone sounds. A
condition for automatic release of the electric parking brake is not
fulfilled (Y page 209).
You are driving with the electric parking brake applied.
X Release the electric parking brake manually. 318
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions !
Turn on the igni‐ Turn on the igni‐
tion to release tion to release
the parking brake the parking brake The red
!indicator lamp lights up.
You attempted to release the electric parking brake while the igni-
tion was switched off.
X Switch the ignition on. J
Check brake fluid Check brake fluid
level level There is insufficient brake fluid in the brake fluid reservoir.
In addition, the red Jwarning lamp lights up in the instrument
cluster and a warning tone sounds.
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 circumstances.
X Secure the vehicle against rolling away (Y page 207).
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the fault. #
Check brake pad Check brake pad
wear wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
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:
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 207).
X Restart the engine. 322
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Blind Spot Assist
Blind Spot Assist
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual
orActive
Active
Blind Spot Assist
Blind Spot Assist
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual Blind Spot Assist or Active Blind Spot Assist is temporarily inop-
erative. Possible causes:
R the 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 sta-
tions or other sources of electromagnetic radiation
Once the causes listed above no longer apply, the display message goes out.
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 to prevent it from rolling away (Y page 207).
X Restart the engine. Blind Spot Assist Blind Spot Assist
not not
available
available when
when
towing a trailer
towing a trailer
See See Owner's
Owner's Manual
Manual
or Active Blind
Active Blind
Spot Assist not
Spot Assist not
available available when
whentow‐
tow‐
ing a trailer See
ing a trailer See
Owner's Manual Owner's Manual Blind Spot Assist or Active Blind Spot Assist is deactivated while
towing a trailer.
You have established the electrical connection between the trailer
and your vehicle.
X Press aon the steering wheel to confirm the display mes-
sage. Blind Spot Assist Blind Spot Assist
inoperative inoperative
or
Active Blind Spot
Active Blind Spot
Assist inoperative Assist inoperative Blind Spot Assist or Active Blind Spot Assist is faulty.
X Visit a qualified specialist workshop. Park
Park
Assist
Assist cancel‐
cancel‐
led
led The driver's door is open.
X Repeat the parking gap measurement and parking process with
the driver's door closed. You touched the multifunction steering wheel while steering inter-
vention was active.
X While steering intervention is active, make sure not to touch the
multifunction steering wheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 239). Display
messages
339On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Park
Park
Assist
Assist inoper‐
inoper‐
ative
ative PARKTRONIC is malfunctioning or faulty.
X Follow the instructions and helpful hints in the "Problems with
PARKTRONIC" section (Y page 239).
If the display message continues to be displayed: X Visit a qualified specialist workshop. Active Parking Assist is unavailable or faulty.
X Switch off the ignition and restart the engine.
If Active Parking Assist continues to be unavailable (the jsymbol
is not shown in the multifunction display):
X Visit a qualified specialist workshop. Traffic Sign Traffic Sign
Assist currently Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual Traffic Sign Assist is temporarily inoperative.
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
X Clean the windscreen.
If the system detects that the camera is fully operational, the dis-
play message disappears.
Traffic Sign Assist is operational again. Traffic Sign Traffic Sign
Assist inoperative Assist inoperative Traffic Sign Assist is faulty.
X Visit a qualified specialist workshop. ë
Off Off The HOLD function is deactivated. The vehicle is skidding.
A warning tone also sounds.
X Reactivate the HOLD function later (Y page 232). The HOLD function is deactivated. When the brake pedal is firmly
depressed, an activation condition is not fulfilled.
A warning tone also sounds.
X Check the activation conditions for the HOLD function
(Y page 232). DISTRONIC PLUS off DISTRONIC PLUS off DISTRONIC PLUS has been deactivated (Y
page 222).
If it was not deactivated by the driver, a warning tone also sounds. DISTRONIC PLUS
DISTRONIC PLUS
available again available again DISTRONIC PLUS is operational again after having been tempo-
rarily unavailable. You can now reactivate DISTRONIC PLUS
(Y
page 222). 340
Display
messagesOn-board computer and displays

Work on the battery, e.g. removing or fitting,
requires specialist knowledge and the use of
special tools. Therefore, always have work on the battery carried out at a qualified specialist
workshop. G
WARNING
Work carried out incorrectly on the battery
may lead to a malfunction, e.g. a short circuit. This, in turn, may restrict the functions of the
safety-relevant systems, e.g. the lighting sys-
tem, ABS (Anti-lock Braking System) or ESP ®
(Electronic Stability Program). The operating
safety of your vehicle may then be compro-
mised. You could then lose control of the vehi-
cle, e.g.:
R when braking
R when making sudden steering movements
and/or travelling at an inappropriate
speed.
There is a risk of an accident.
In the event of a short circuit or similar situa-
tion, inform a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car- ried out at a qualified specialist workshop.
i For further information about ABS and
ESP ®
, see (Y page 74) and (Y page 80). G
WARNING
Electrostatic build-up can lead to the creation of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle body to remove any existing electrostatic
build-up.
The highly flammable gas mixture is created
while the battery is charging and when jump-
starting. Always make sure that neither you nor the
battery is electrostatically charged. Electro-
static charge is created, for example:
R by wearing synthetic fibre clothing
R due to friction between clothing and the
seat
R when you pull or push the battery across
carpet or other synthetic materials
R when you rub the battery with a cloth G
WARNING
During the charging process, a battery produ- ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a
connected battery does not come into con-
tact with vehicle parts.
R Never place metal objects or tools on a bat-
tery.
R It is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery.
R When jump-starting, make sure that the
battery poles with identical polarity are
connected.
R It is particularly important to observe the
described order when connecting and dis-
connecting the jump leads.
R Never connect or disconnect the battery
terminals while the engine is running. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. H
Environmental note Batteries contain pollutants.
It is illegal to dispose of them
with the household rubbish.
They must be collected sep- Battery (vehicle)
413Breakdown assistance
Z

arately and disposed of in an
environmentally responsible
recycling system. Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used batter-
ies.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Service
Booklet or contact a qualified specialist
workshop for more information.
! Always have work on the batteries carried
out at a qualified specialist workshop.
Should it, in exceptional circumstances, be absolutely necessary to disconnect the 12-
volt battery yourself, please observe the
following:
R secure the vehicle to prevent it from roll-
ing away.
R switch off the engine and remove the
key. Make sure the ignition is switched
off. Check that all the indicator lamps in
the instrument cluster are off. Otherwise,
you may damage electronic components such as the alternator, for example.
R first, disconnect the negative terminal
clamp, followed by the positive terminal
clamp. Never swap the terminal clamps.
The vehicle electronics may otherwise be
damaged.
R the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The batteries and the covers of the positive
terminal clamps must always be fitted
securely during operation.
Comply with safety precautions and take pro-
tective measures when handling batteries. Comply with safety precautions and take pro-
tective measures when handling batteries. WARNING
Fire, naked flames and smoking
are prohibited when handling the
battery. Avoid creating sparks. Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing.
Wear suitable protective clothing,
in particular gloves, an apron and a face mask.
Immediately rinse acid splashes
off with clean water. Consult a doc-tor if necessary. Wear eye protection.
Keep children away.
Observe this Owner's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event of
an accident.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop. You can also charge the battery with a
charger recommended by Mercedes-Benz. 414
Battery (vehicle)Breakdown assistance

For more information, please contact a quali-
fied specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
When you park the vehicle, remove the key if you do not require any electrical consumers.
The vehicle will then use very little energy,
thus conserving battery power.
Hybrid vehicles: if the battery charge is suf-
ficient, the high-voltage battery can also sup- ply the 12 V battery with energy. This only
happens if the battery charge of the 12 V bat-
tery requires this, e.g. after using electrical
consumers for an extended period with the
engine switched off. As the on-board voltage
is continuously monitored this can also be
performed when the engine is switched off.
The battery charge of the 12 V battery and the
on-board voltage are thereby kept stable for a
longer period. High-voltage battery - important
safety notes
Only hybrid vehicles are equipped with a high-
voltage battery. G
DANGER
The vehicle's high voltage electrical system is under high voltage. If you modify components
in the vehicle's high-voltage electrical system or touch damaged components, you may be
electrocuted. The components in the vehi-
cle's high-voltage electrical system may be
damaged in an accident, although the damage
is not visible. There is a risk of fatal injury.
Do not touch any high-voltage components
after an accident and never modify the vehi-
cle's high-voltage electrical system. Have the vehicle towed away after an accident and the vehicle's high-voltage electrical system
checked by a qualified specialist workshop. G
WARNING
In the event of a vehicle fire, the internal pres- sure of the high-voltage battery could exceeda critical value. In this case, flammable gas
escapes through a vent valve in the vehicle's
underbody. The gas can ignite. There is a risk
of injury.
Leave the danger area immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements. G
WARNING
If the housing of the high-voltage battery has
been damaged, electrolyte and gases may
leak out. These are poisonous and caustic.
There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Immediately rinse electrolyte splashes off
with water and seek medical attention
straight away.
! Only charge the high-voltage battery in
the "Charging when stationary" operating
mode. Do not connect a battery charger to
the high-voltage battery. Otherwise, the
vehicle's high-voltage electrical system
could be damaged.
! Exhaustive discharge caused by the vehi-
cle standing idle for lengthy periods can
damage the high-voltage battery.
If the vehicle is idle for lengthy periods, run
it for a few minutes once every six weeks to
charge up the high-voltage battery.
During the charging process, switch off all
electrical consumers, e.g. the automatic
climate control or the seat heating.
If you wish to park your vehicle for several
weeks, ensure that the battery is at least 30 %
charged. If necessary, charge the high-volt-
age battery while stationary before parking
the vehicle (Y page 416).
Consult a Mercedes-Benz Service Centre if
you wish to leave your vehicle parked up for a
long period of time. Battery (vehicle)
415Breakdown assistance Z

Charging the 12 V battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only charge the battery using the jump-
start connection point.
The jump-starting connection point is in the
engine compartment (Y page 418).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure (Y page 418).
Never charge the battery if it is still fitted to
the vehicle, unless you use a battery charger which has been tested and approved by
Mercedes-Benz. A battery charger unit spe-
cially adapted for Mercedes-Benz vehicles
and tested and approved by Mercedes-Benz is available as an accessory. This device per-
mits charging of the battery in position. Con-
tact a Mercedes-Benz Service Centre for
information and availability. Read the battery charger's operating instructions before
charging the battery.
If the indicator/warning lamps do not light up
at low temperatures, it is very likely that the
discharged battery has frozen. In this case
you may neither jump-start the vehicle nor
charge the battery. The service life of a bat-
tery that has been thawed may be reduced.
The starting characteristics may be impaired, especially at low temperatures. Have the
thawed battery checked at a qualified spe-
cialist workshop.
Hybrid vehicles: if the battery charge is suf-
ficient, the high-voltage battery can also sup-
ply the 12 V battery with energy. This only
happens if the battery charge of the 12 V bat-
tery requires this, e.g. after using electrical
consumers for an extended period with the
engine switched off. As the on-board voltage
is continuously monitored this can also be
performed when the engine is switched off.
The battery charge of the 12 V battery and the
on-board voltage are thereby kept stable for a longer period. Charging the high-voltage battery
when stationary
Only hybrid vehicles are equipped with a high-
voltage battery. G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
! Only charge the high-voltage battery in
the "Charging when stationary" operating
mode. Do not connect a battery charger to
the high-voltage battery. Otherwise, the 416
Battery (vehicle)Breakdown assistance