2018 MERCEDES-BENZ GLS SUV jump start

Charging the 12 V battery
GWARNING
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.
GWARNING
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.
GWARNING
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 (
Ypage 346).
XOpen the hood.
XConnect 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 (
Ypage 346).
Keep away from fire and open flames. Do not
lean over a battery. Never charge the battery if it
is still installed in the vehicle, unless you use a
battery charger which has been tested and
approved by Mercedes-Benz. A battery charger
unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. It permits the
charging of the battery in its installed position.
Contact an authorized Mercedes-Benz Center
for further information and availabilit y. Read t
he
battery charger's operating instructions before
charging the battery.
If, at low temperatures, the indicator lamps/
warning lamps in the instrument cluster do not
light up, it is highly 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 thawed-out battery may be
shorter. The starting characteristics can be
impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified
specialist workshop.
Jump-starting
For the jump-starting procedure, use only the jump-starting connection point in the engine com-
partment, consisting of a positive terminal and a ground point.
GWARNING
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.
GWARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
346Jump-starting
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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.
GWARNING
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.
RMake sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
RNever place metal objects or tools on a battery.
RIt is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
RWhen jump-starting, make sure that the battery poles with identical polarity are connected.
RIt is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
RNever connect or disconnect the battery terminals while the engine is running.
GWARNING
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.
!Vehicles with a gasoline engine: avoid repeated and lengthy starting attempts. Otherwise, the
catalytic converter could be damaged by non-combusted fuel.
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 thawed-out battery may be shorter. The starting characteristics can be
impaired, particularly at low temperatures. Have the thawed-out battery checked at a qualified
specialist workshop.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a donor battery using jumper cables.
Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a donor battery or a jump-starting device.
RVehicles with a gasoline engine: only jump-start the vehicle when the engine and exhaust
system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the battery slightly.
RMake sure that the two vehicles do not touch.
Jump-starting347
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Make sure that:
RThe jumper cables are not damaged.
RBare parts of the terminal clamp do not come into contact with other metal parts while the jumpercables are connected to the battery.
RThe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position j.
XMake sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position uin the ignition lock and remove it
(
Ypage 140).
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
iRight-hand-drive vehicle: the jump-starting connection points may be located on the other
side of the vehicle.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XSlide cover :of positive terminal ;in the direction of the arrow.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jumper cable, always begin with positive terminal ;on your own vehicle first.
XStart the engine of the donor vehicle and run it at idling speed.
XConnect negative terminal ?of donor battery Bto ground point Aof your vehicle using the
jumper cable, beginning with donor battery Bfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Aand negative terminal ?, then from pos-
itive terminal ;and positive terminal =. Begin each time at the contacts on your own vehicle
first.
XClose cover :of positive terminal ;after removing the jumper cables.
XHave the battery checked at a qualified specialist workshop.
Jump-starting is not considered to be a normal operating condition.
348Jump-starting
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iJumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
Functions relevant to safety are restricted or
no longer available if:
Rthe engine is not running.
Rthe brake system or the power steering is
malfunctioning.
Rthere is a malfunction in the voltage supply or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely.
GWARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the:
Rthe towing eye could detach itself
Rthe vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate (
Ypage 385).
!When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations:
Rwhen towing the vehicle
Rin the car wash
!Make sure that the electric parking brake is
released. If the electric parking brake is faulty,
visit a qualified specialist workshop.
!Only secure the tow rope or tow bar at the
towing eyes, or the trailer tow hitch, if availa-
ble. You could otherwise damage the vehicle.
!Observe the following points when towing
with a tow rope:
RSecure the tow rope on the same side on
both vehicles.
RMake sure that the tow rope is not longer
than legally permitted. Mark the tow rope in
the middle, e.g. with a white c
loth
(11.8 x 11.8 in). This will make other road
users aware that a vehicle is being towed.
ROnly secure the tow cable to the towing
eyes or, if available, to the trailer tow hitch.
RObserve the brake lamps of the towing
vehicle while driving. Always maintain a dis-
tance a distance so that the tow rope does not sag.
RDo not use steel cables or chains to tow
your vehicle. You could otherwise damage
the vehicle.
!Do not use the trailer tow hitch for recovery
or towing. Do not use the towing eye for
recovery. this could damage the vehicle. If in
doubt, have the vehicle recovered using a
crane.
!When towing, pull away slowly and
smoothly. Pull the towed vehicle as straight as
possible and not at an acute angle. Excessive
tractive power could damage the vehicles.
When towing, it is preferable to use a rigid tow-
ing bar as opposed to a tow rope. A rigid towing bar helps to keep the tractive power low.
!When towing away vehicles with KEYLESS-
GO, use the key instead of the Start/Stop
button. The automatic transmission may oth-
erwise shift to position jwhen you open the
driver's or front-passenger door, which could
damage the transmission.
!Do not tow with sling-type equipment. This
could damage the vehicle.
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Vehicles with 4MATIC may either be towed away
with both axles on the ground or be loaded up
and transported.
If the vehicle's transmission, front, or rear axle is
damaged, have the vehicle transported on a
truck or trailer.
In the event of damage to the electrical sys-
tem:if the battery is defective, the automatic
transmission will be locked in position P. To shift
the automatic transmission to position N, you
must provide power to the vehicle's electrical
system in the same way as when jump-starting
(
Ypage 346).
Have the vehicle transported on a transporter or
trailer.
Tow-starting (emergency engine
starting)
!
Vehicles with automatic transmission must
not be tow-started. You could otherwise dam-
age the automatic transmission.
You can find information on "Jump-starting"
under (
Ypage 346).
Fuses
Important safety notes
GWARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher amper- age, the electric cables could be overloaded.
This could result in a fire. There is a risk of an
accident and injury.
Always replace faulty fuses with the specified
new fuses having the correct amperage.
!For the fuse boxes in the engine compart-
ment and under the rear bench seat, only use
fuses with the suffix "S". Otherwise, compo-
nents or systems could be damaged.
!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. The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the compo-
nents on the circuit and their functions stop
operating.
Blown fuses must be replaced with fuses of the
same rating, which you can recognize by the
color and value. The fuse ratings are listed in the
fuse allocation chart.
The fuse allocation chart is located in the fuse
box under the rear bench seat (
Ypage 353).
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified special-
ist workshop, e.g. an authorized Mercedes-Benz
Center.
Before changing a fuse
Observe the important safety notes
(Ypage 352)
XSwitch off the engine.
XSwitch off all electrical consumers.
XRemove the SmartKey from the ignition lock.
Or, on vehicles with KEYLESS-GO start function
or KEYLESS‑GO:
XOpen the driver's door.
The vehicle electronics are now in key posi-
tion u. This is the same as the SmartKey
having been removed.
The driver’s door can be closed again.
XSecure the vehicle against rolling away
(Ypage 161).
All indicator lamps in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
RFuse box on the front-passenger side of the
dashboard
RFuse box in the engine compartment on the
right-hand side of the vehicle, when viewed in
the direction of travel
RFuse box under the rear bench seat
Dashboard fuse box
!
Do not use a pointed object such as a screw-
driver to open the cover in the dashboard. You
could damage the dashboard or the cover.
Mercedes-Benz recommends that you have this
work performed at a qualified specialist work-
352Fuses
Breakdown assistance