2015 MERCEDES-BENZ B-CLASS HATCHBACK check engine

Charging the 12‑
volt batteryG
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 breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. 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 maximum
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 258).
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 258).
If the indicator/warning lamps do not light up at
low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has
been thawed may be reduced. The starting char-
acteristics may be impaired, especially at low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Only charge the installed battery with a battery
charger which has been tested and approved by
Mercedes-Benz. A battery charger unit specially
adapted for Mercedes-Benz vehicles and tested
and approved by Mercedes-Benz is available as an accessory. This device permits charging of
the battery in position. Contact a Mercedes-
Benz Service Centre for information and availa-
bility. Read the battery charger's operating
instructions before charging the battery. High-voltage battery - important
safety notes
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. 256
BatteriesBreakdown assistance

The vehicle's high-voltage electrical system is
under high voltage.
R Do not handle high-voltage components or
the orange cables of the vehicle's high-volt-
age electrical system.
R Do not touch high-voltage components or the
orange cables of the high-voltage electrical
system when a vehicle has been involved in a
crash.
R Do not touch any damaged components or
the damaged orange cables of the vehicle's
high-voltage electrical system.
R Do not remove the covers of the high-voltage
electrical system components that are
marked with a warning sticker.
Do not leave the vehicle parked for longer than
14 days with a high-voltage battery charge sta-
tus below 20%.
You can check the charge status in the charge
level display (Y page 174).
If you park the vehicle and leave it stationary for
longer periods, connect it to a power supply.
If you leave the vehicle parked up for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked up for longer than
six weeks, it may suffer from lack of use.
X Visit a qualified specialist workshop and seek
advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop.
i Very low or very high outside temperatures
can impair the function of the high-voltage
battery (Y page 136). This can also occur
when the vehicle engine is switched off
(Y page 136). Batteries
257Breakdown assistance Z

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a pos- itive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not breathe in any battery gases. Do not lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off battery acid
thoroughly with plenty of clean water and seek medical attention at once. 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
During the charging process, a battery produces 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 contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described 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 disconnecting
the jump leads.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting 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.
! Avoid repeated and lengthy starting attempts.
Do not use a rapid-charging device to start the engine.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has been thawed may be reduced. Have the thawed battery checked at a qualified specialist workshop.
If the 12 V battery is discharged, or after the vehicle has been jump-started, the Without chang‐ Without chang‐
ing
ing gear,
gear, consult
consult workshop
workshop message appears. There is a malfunction in the on-board voltage.
Visit a qualified specialist workshop immediately.
The drive system cannot be started if the 12 V battery is discharged. This is not dependant on
whether the high-voltage battery is charged or not. The vehicle cannot be jump-started if the high-
voltage battery is discharged. The high-voltage battery must first be charged. 258
Jump-startingBreakdown assistance

The fuse allocation chart is on the fuse box in the
front-passenger footwell (Y page 264).Fuse box in the engine compartment
G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it is
lying correctly on the fuse box. Moisture seep-
ing in or dirt could otherwise impair the oper- ation of the fuses. X
Open the bonnet.
X Remove any existing moisture from the fuse
box using a dry cloth.
X To open: unclip bonnet release cable ?from
bracket =.
X Open retaining clamps ;.
X Fold cover :up in the direction of the arrow
and remove it. X
To close: check whether the seal is lying cor-
rectly in cover :.
X Insert cover :at the back into openings A
on the fuse box.
X Slide bonnet release cable ?to the side and
hold if necessary.
X Fold down cover :.
X Clip bonnet release cable ?into bracket =.
X Hook clamps ;into the fuse box and close.
X Close the bonnet. Fuse box in the front-passenger foot-
well
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it is
lying correctly on the fuse box. Moisture seep-
ing in or dirt could otherwise impair the oper- ation of the fuses. X
To open: open the front-passenger door.
X Remove the floormat.
X Fold out perforated floor covering :in the
direction of the arrow. 264
Electrical fusesBreakdown assistance

i
The coolant is checked at every mainte-
nance interval at a qualified specialist work-
shop. Windscreen washer system and head-
lamp cleaning system
Important safety notes G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure the windscreen washer concen-
trate does not come into contact with the filler neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or MB
WinterFit. Unsuitable washer fluid could dam-
age the plastic lenses of the headlamps.
! Do not use distilled or de-ionised water in
the washer fluid reservoir. Otherwise, the
level sensor may be damaged.
! Only the washer fluids SummerFit and Win-
terFit can be mixed. Otherwise, the spraying
nozzles could become blocked.
Comply with the important safety notes for ser-
vice products when handling washer fluid
(Y page 282).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture of
water and washer fluid, e.g. MB SummerFit.
Mix 1 part MB SummerFit to 100 parts water.
At temperatures below freezing:
X Fill the washer fluid reservoir with a mixture of
water and washer fluid, e.g. MB WinterFit.
For the correct mixing ratio refer to the infor-
mation on the antifreeze reservoir.
i Add washer fluid concentrate, e.g. MB Sum-
merFit or MB WinterFit, to the washer fluid all
year round. Vehicle data
General notes
Please note that for the specified vehicle data: R the heights specified may vary as a result of:
- tyres
- load
- condition of the suspension
- optional equipment
R optional equipment reduces the maximum
payload
R vehicle-specific weight information can be
found on the vehicle identification plate
(Y page 281).
R only for certain countries: you can find vehi-
cle-specific vehicle data in the COC docu-
ments (CERTIFICATE OF CONFORMITY).
These documents are delivered with your
vehicle.
R The range values were determined in the
respective, currently valid version according
to Regulation (EC) No. 715/2007.
The range depends on the drive program selec-
ted and can vary due to:
R higher and lower outside temperatures
R the style of driving
R activated electrical consumers
i Information on the range can be found in the
Trip Trip menu (Y page 178). Dimensions and weights284
Vehicle dataTechnical data