charging MERCEDES-BENZ B-Class 2017 W246 Owner's Guide

X
Drive to the nearest qualified specialist work-
shop and have the tire changed there.
X Have the tire sealant bottle and the filler hose
replaced as soon as possible at a qualified
specialist workshop.
X Have the tire sealant bottle replaced every
four years at a qualified specialist workshop. Batteries
12 V battery – important safety notes
Special tools and expert knowledge are required
when working on the batteries, e.g. removal and installation. You should therefore have all work
involving the batteries carried out at a qualified
specialist workshop. G
WARNING
The battery terminal clamps can remain under voltage even after being disconnected. If work
on the battery is carried out incorrectly, a
short-circuit may result. There is a risk of fire.
Always have work on the batteries carried out
at a qualified specialist workshop. Never dis-
connect a battery yourself. G
WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This can lead to function restrictions applying to
safety-relevant systems, e.g the lighting sys-
tem, the ABS (anti-lock braking system) or the
ESP ®
(Electronic Stability Program). The oper-
ating safety of your vehicle may be restricted.
You could lose control of the vehicle, for
example:
R when braking
R in the event of abrupt steering maneuvers
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci-
dent, contact 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.
For further information about ABS and ESP ®
,
see (Y page 59) and (Y page 62). 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 forms when
charging the battery as well as when jump-start- ing.
Always make sure that neither you nor the bat-
tery is electrostatically charged. A build-up of
electrostatic charge can be caused, for exam-
ple:
R by wearing clothing made from synthetic
fibers
R due to friction between clothing and seats
R if you push or pull the battery across the car-
pet or other synthetic materials
R if 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. 246
BatteriesBreakdown assistance

find further information in the separate operat-
ing instructions. Charging the 12‑volt 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, open 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 skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten- tion. 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-
starting connection point.
The jump-starting connection point is in the
engine compartment (Y page 249).
X Open the hood.
X Connect the battery charger to the positive
terminal and ground point in the same order
as when connecting the donor battery in the
jump-starting procedure (Y page 249).
If the indicator/warning lamps do not light up in
the instrument cluster at low temperatures, it is very likely that the discharged battery has fro-
zen. In this case you may neither jump-start the vehicle nor charge the battery. The service life of
a thawed-out battery may be shorter. The start-ing characteristics can be impaired, particularly at low temperatures. Have the thawed-out bat-
tery checked at a qualified specialist workshop.
Only charge the installed battery with a battery
charger which has been tested and approved byMercedes-Benz. A battery charger unit specially
adapted for Mercedes-Benz vehicles and tested
and approved by Mercedes-Benz is available as an accessory. It permits the charging of the bat-tery in its installed position. Contact an author-
ized Mercedes-Benz Center for further informa- tion and availability. Read the battery charger's
operating instructions before charging the bat-
tery. 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.
Following an accident, do not touch any high- voltage components and never modify the
vehicle'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 can exceed a
critical value. In this case flammable gas
escapes through a ventilation valve on the
underbody. The gas can ignite. There is a risk of injury.
Leave the danger zone immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements. 248
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 condition of
charge below 20%.
You can check the condition of charge in the
charge level display (Y page 153). If you park the vehicle and leave it stationary for
longer periods, connect it to a power supply.
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than six weeks, the vehicle may suffer damage as a
result of 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 119). This can also occur
when the vehicle engine is switched off
(Y page 119). Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a pos- itive terminal and a ground point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the
battery. Keep children away from batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient ven-
tilation 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. Jump-starting
249Breakdown assistance
Z

R
It is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
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 in the instrument cluster at low temperatures, it is very likely that the discharged battery has frozen. In this case you may neither jump-start the vehicle norcharge the battery. The service life of a thawed-out battery may be shorter. Have the thawed-out
battery checked at a qualified specialist workshop.
If the 12 V battery is discharged, or after the vehicle has been jump-started, the Service
Service
Required Required Do
DoNot
Not Shift
Shift Gears
GearsVisit
VisitDealer
Dealer 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 dependent 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 be charged first.
The drive system can be started using another vehicle. R Only use batteries with an equal nominal voltage (12 volts).
R Make sure that the battery of the donor vehicle does not have a significantly lower capacity than
the discharged battery.
R Use jumper cables with a sufficient cross-section and insulated terminal clamps from a qualified
specialist workshop, e.g. an authorized Mercedes-Benz Center.
R Make sure that the two vehicles do not touch.
R Route the jumper cables so that they cannot be caught by rotating components in the engine
compartment.
R Do not disconnect the discharged battery from the vehicle's electrical system. 250
Jump-startingBreakdown assistance

!
Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could be
damaged.
! Observe the following points when towing
with a tow rope:
R Secure the tow rope on the same side on
both vehicles.
R Ensure that the tow cable is not longer than
legally permitted. Mark the tow cable in the
middle, e.g. with a white cloth (30 x 30 cm). This will make other road users aware that
the vehicle is being towed.
R Only secure the tow cable to the towing
eye.
R Observe the brake lamps of the towing
vehicle while driving. Always maintain a dis-
tance so that the tow rope does not sag.
R Do not use steel cables or chains to tow
your vehicle. You could otherwise damage
the vehicle.
! Do not use the towing eyes for recovery pur-
poses as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! When towing, pull away slowly and
smoothly. If the tractive power is too high, the vehicles could be damaged.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of 30 mph
(50km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the front axle must be raised
or the entire vehicle raised and transported.
! Do not tow with sling-type equipment. This
could damage the vehicle.
! To tow vehicles with KEYLESS-GO, use the
SmartKey instead of the Start/Stop button.
The transmission may otherwise shift to posi- tion Pwhen you open the driver's or front-
passenger door, which could damage the
transmission.
Observe the legal requirements for the relevant countries when towing away.
Make sure that no charging cable is plugged in.
The parking lock cannot be released if a charg-
ing cable is plugged in.
It is better to have the vehicle transported than
to have it towed away. If the vehicle can no longer be driven because of
an accident or breakdown, you have the follow-
ing options:
R transporting the vehicle
As a rule, you should have the vehicle trans-
ported.
R towing the vehicle with a tow rope or tow bar
Only tow the vehicle in exceptional cases.
Observe the following notes.
The vehicle may not be towed and must always be transported if:
R the multifunction display is not working
R one of more of the following warning lamps is
lit up:
- Drive system
- 12 V battery
R one or both of the following display messages
have appeared:
- Stop Switch Engine Off
Stop Switch Engine Off
- Service Required Do Not Shift Service Required Do Not Shift
Gears Visit Dealer Gears Visit Dealer
R you have to tow the vehicle over a longer dis-
tance than 30 miles (50 km).
The battery must be connected and charged.
Otherwise, you:
R cannot turn the SmartKey to position 2in the
ignition lock
R cannot release the electric parking brake
R cannot move the transmission to position N
The function of the electric parking brake and
the parking lock is dependent on the on-board
voltage.
If the on-board voltage is low or if there is a sys- tem malfunction:
R the electric parking brake may not be applied
in certain circumstances, or
R the transmission may not be shifted to P
Switch off non-essential consumers, e.g. the
radio.
Disarm the automatic locking feature before the
vehicle is towed (Y page 166). You could other-
wise be locked out when pushing or towing the
vehicle. 252
TowingBreakdown assistance