2019 MERCEDES-BENZ GLS SUV service

te
ry. Begin ea chtime wi th the conta cts on
yo ur ow nve hicle firs t. #
Afterre moving the jump lead/charging
cable, close co ver1 of positive clamp 2.
Fu rther information can be obtained at a quali‐
fi ed specialist workshop. Re
placing the 12V battery #
Obser vethe no tes on the12 V battery
(/ page 557).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a qualified specialist
wo rkshop, e.g. at a Mercedes-Benz Service
Centre.
Obser vethefo llowing no tes if youwa ntto
re place the battery yourself:
R Alw aysre place a faulty bat tery with a battery
which meets the specific vehicle require‐
ments. The
vehicle is equipped with an AGMtech nol‐
ogy battery (Absorbent Glass Mat) or a li th‐
ium-ion batter y.Fu llve hicle functionality is
only guaranteed with an AGM battery or lith‐
ium-ion batter y.Fo r saf etyre asons,
Mercedes-Benz recommends that you on ly
use bat teries which ha vebeen tested and
appr ovedfo ryo ur vehicle byMercedes-Benz.
R Carryove r de tach able parts, such as vent
hoses, elbow fittings or term inal co vers from
th e battery being replaced.
R Make sure that theve nt hose is al ways con‐
nected tothe original opening on the side of
th e batter y.
Fit any existing or supplied cell caps.
Otherwise, gases or battery acid could
escape.
R Make sure that de tach able parts are recon‐
nected in the same way. To
w- starting or towing away Pe
rm itted towing me thods Mercedes-Benz
recommends transporting your
ve hicle in the case of a breakdown, rath er than
to wing it away.
Fo rto wing, use a tow rope or tow bar with bo th
axles on the ground. Do not use tow bar sys‐
te ms.
* NO
TEDama getotheve hicle due to tow‐
ing away incor rectly #
Obser vethe instructions and no tes on
to wing away. 562
Breakdown assis tance

Obser
vethe no tes on electrical fuses
(/ page 567).
Opening &
WARNING Risk of inju ryfrom using the
windscreen wipers while the engine bon‐
net is open
When the engine bonn etis open, and the
windscreen wipers are set in motion, you can
be trapped bythe wiper linkage. #
Alw ays switch off the windscreen wip‐
ers and ignition before opening the
engine bonn et. #
Remo veany existing moisture from the fuse
box using a dry clo th. #
Loosen scr ews2 and remo vefuse box lid
1 from theto p.
Closing #
Check whe ther the seal is positioned cor‐
re ctly in the lid. #
Insert the lid into the brac ket at there ar of
th e fuse box. #
Fold down the lid of the fuse box and tighten
scr ews2. #
Close the bonn et. Opening and closing
the fuse box in the
cockpit The fuse box is on
the side of the dashboard
under a co ver. #
Con tact a Mercedes-Benz Service Centre for
fur ther information. Opening and closing
the fuse box in the front
passenger foot we ll #
Contact a Mercedes-Benz Service Cent refor
fur ther information. Opening and closing
the fuse box in the load
compa rtment Obse
rveth e no tes on electrical fuses
(/ page 567). 568
Breakdown assis tance

Note
s on noise or unusual handling charac‐
te rist ics
While driving, pay attention tovibrations, noises
and unusual handling characteristics, e.g. pulling
to one side. This may indicate that the wheels or
tyres are damaged. If you suspect that a tyre is
defective, reduce your speed immediatel y.Stop
th eve hicle as soon as possible tocheck the
wheels and tyres for dama ge. Hidden tyre dam‐
age could also be causing the unusual handling
ch aracteristics. If youfind no signs of damage,
ha ve the tyres and wheels checked at a qualified
specialist workshop. Note
s onregular lyinspecting wheels and
tyres &
WARNING Risk of accident from dam‐
aged tyres
Dama ged tyres can cause tyre pressure loss.
As a result, you could lose cont rol of your
ve hicle. #
Check the tyres regularly for signs of
dama geand replace any damaged tyres
immediatel y. Car
ryout thefo llowing checks on all wheels reg‐
ularly, at least once a month or as requ ired, e.g.
prior toa long journey or driving off- road:
R Check the tyre pressure (/ page571).
R Visually inspect tyres and wheels for dam‐
age.
R Check theva lve caps.
The valves must be pr otected against mois‐
ture and dirt bytheva lve caps appr oved
especially foryo ur vehicle byMercedes-Benz.
R Visual check of the tyre tread dep thand the
tyre contact su rface across the entire width.
The minimum tread dep thfor summer tyres
is 3 mm and for winter tyres 4 mm. Note
s on snow chains
* NO
TEDama getocomponents of the
ve hicle body or chassis due tofitted
snow chains If
yo ufit snow chains tothe front wheels of
4MATIC vehicles, you may damage co mpo‐
nents of theve hicle body or chassis. #
Onlyfit snow chains tothere ar wheels
of 4MATIC vehicles. *
NO
TEDama getothe wheel trim from fit‐
te d snow chains If sn
ow ch ains are fitted tosteel wheels, the
wheel trims can be damaged. #
Remo vethe wheel trims of steel wheels
before fitting snow chains. R
Snow chains are on ly permissible for cer tain
wheel/tyre combinations. You can obtain
information about this from a Mercedes-Benz
Service Cent re. 57 0
Wheels and tyres

R
For saf etyre asons, on lyuse sn ow chainsthat
ha ve been specifically appr oved foryo ur
ve hicle byMercedes-Benz, or snow chains
with the same quality standard.
R If sn ow ch ains are fitted, the maximum per‐
missible speed is 50 km/h.
R Vehicles with Active Parking Assis t:do
not use Active Parking Assist when snow
ch ains are fitted.
R Vehicles with AIRMATIC or E- ACTIVE
BO DY CONT ROL:if snow chains are fitted,
only drive at raised vehicle le vel .
% You can permanently limit the maximum
ve hicle speed for driving with winter tyres
(/ page 245).
% You can deactivate ESP ®
to pull away
( / page 234). This allo wsthe wheels to
spin, achieving an increased driving forc e. Ty
re pressure Note
s on tyre pressure &
WARNING Risk of accident due toinsuf‐
fi cient or excessive tyre pressure
Underinfla ted or overinfla ted tyres pose the
fo llowing risks:
R The tyres may bur st, especially as the
load and vehicle speed increase.
R The tyres may wearexc essively and/or
une venly, which may greatlyimpair tyre
traction.
R The driving characteristics, as well as
st eering and braking, may be greatly
impaired. #
Comply with there commended tyre
pressure and check the tyre pressure of
all tyres including the spare wheel regu‐
larly:
R at least once a month
R when the load changes R
before embarking on a lon ger journey
R if operating conditions change, e.g. off-
ro ad driving #
Adjust the tyre pressure as necessar y. Ty
re pressure which is too high or too low can:
R Shor tenth e service life of the tyres.
R Cause increased tyre damage.
R Adversely af fect driving characteristics and
th us driving saf ety, e.g. due toaquaplaning. &
WARNING Risk of accident from repea‐
te d tyre pressure drop
If th e tyre pressure drops repeatedly, the
wheel, valve or tyre may be damaged.
Insuf ficient tyre pressure can cause the tyres
to bur st. #
Inspect the tyre for signs of fore ign
objects. #
Check whe ther the wheel or valve has a
leak. Wheels and tyres
571

Ty
re pressure moni toring sy stem Fu
nction of the ty repressure moni toring sys‐
tem
The sy stem checks the tyre pressure and the
tyre temp erature of the tyres fitted totheve hicle
by means of a tyre pressu resensor.
New tyre pressure sensors, e.g. in winter tyres,
are automatically taught-in during thefirs t jour‐
ney they are used.
The tyre pressure and the tyre temp erature
appear in the multifunction display
(/ page 573).
If th ere is a subs tantial pressure loss or if the
tyre temp erature is excessive, you will be
wa rned in thefo llowing ways:
R via display messa ges
( / page
64 9)
R viatheh warning lamp in the instrument
clus ter (/ page675)
The tyre pressu remonitoring sy stem is only an
aid. It is the driver's responsibility toset the tyre
pressure tothere commended cold tyre pressure suitable
forth e operating situation. Set the tyre
pressure for cold tyres using a tyre pressu re
ga uge. No tethat the cor rect tyre pressure for
th e cur rent operating situation mu stfirs t be
ta ught-in tothe tyre pressure monitoring sys‐
te m.
In most cases, the tyre pressure monitoring sys‐
te m will auto maticallyupdate the new refere nce
va lues af teryo u ha vechanged the tyre pressure.
Yo u can, ho wever,also update there fere nce val‐
ues byrestarting the tyre pressure monitoring
sy stem manually (/ page574).
Sy stem limits
The sy stem may be impaired or may not function
in thefo llowing situations:
R The tyre pressure has been set incor rectly.
R The reis a sudden pressure loss caused, for
ex ample, byafo re ign object penetrating the
tyre.
R There is a malfunction caused byano ther
ra dio signal source. Make sure
toobser vethefo llowing fur ther rela‐
te d subjec t:
R Notes on tyre pressure (/ page571)
Checking the ty repressure with the tyre
pressure moni toring sy stem
Requ irements:
R The ignition is switched on.
On-board computer: 4 Service 5
Tyres
One of thefo llowing displa ysappears:
R Cur rent tyre pressure and tyre temp erature
of the individual wheels: Wheels and tyres
573

R
Tyre pressures will be displayed after a few
minutes of driving
R Tyre pressure monitor active: thete ach-in
process of the sy stem is not yet compl ete.
The tyre pressures are already being moni‐
to re d. #
Compare the tyre pressure with there com‐
mended tyre pressure forth e cur rent operat‐
ing condition (/ page 572 ). Obse rvethe
no tes on tyre temp erature (/ page571).
% The values displa yed in the multifunction dis‐
play may deviate from those of the tyre pres‐
sure gauge as they referto sea le vel.At high
altitudes, the tyre pressure values indicated
by a pressure gauge are higher than those
shown bythe on-board computer. In this
case, do not reduce the tyre pressure.
Make sure toobser vethefo llowing fur ther rela‐
te d subjec t:
R Notes on tyre pressure (/ page571) Rest
arting the ty repressure moni toring sys‐
tem
Requ irements:
R The recommended tyre pressure is cor rectly
set forth ere spective operating status on
each of thefo ur wheels (/ page571).
Re start the tyre pressure monitoring sy stem in
th efo llowing situations:
R The tyre pressure has changed.
R The wheels or tyres ha vebeen changed or
newly fitted.
On-boa rdcompu ter:
4 Service 5
Tyres #
Swipe down wards on Touch Control on the
left-hand side of thesteering wheel.
The Use current pressures as new reference
values? message is shown in the multifunc‐
tion displa y. #
Tobegin restart, press Touch Control on the
left-hand side of thesteering wheel.
The Tyre press. monitor restarted message is
shown in the multifunction displa y. Cur
rent wa rning messages are dele ted and
th eye llow h warning lamp goes out.
Af teryo u ha vebeen driving for a few
minutes, the sy stem checks whe ther the cur‐
re nt tyre pressures are wi thin the specified
ra nge. The cur rent tyre pressures are then
accep ted as refere nce values and monitored.
Make sure toobser vethefo llowing fur ther rela‐
te d subjec t:
R Notes on tyre pressure (/ page571) 574
Wheels and tyres

or tyres,
the tyre pressure loss warning sy stem
has tobe restar ted (/ page579).
The tyre pressu reloss warning sy stem does not
re place the need toregularly check the tyre
pressures.
Sy stem limitations
The sy stem may be impaired or may not function
particular lyin thefo llowing situations:
R incor rectly set tyre pressure
R sudden pressure loss caused, forex ample,
by afo re ign object penetrating the tyre
R steady pressure loss in se veral tyres
The sy stem has a restricted or del ayed function
particularly in thefo llowing situations:
R poor ground cond itions, e.g. snow or gr avel
R driving with snow chains
R when adopting a very sporty driving style
with high cornering speeds or sudden accel‐
eration
R driving with a very heavy or lar getrailer
R driving wi tha high load Be sure
toalso obse rveth efo llowing fur ther
re lated subjects:
R Notes on tyre pressure (/ page571)
R Displ aymessa ges about the tyres
(/ page
64 9)
Re starting the ty repressure loss warning
sy stem
Re quirements:
R The recommended tyre pressure is cor rectly
set forth ere spective operating status on
each of thefo ur wheels (/ page571).
Re start the tyre pressure loss warning sy stem in
th efo llowing situations:
R The tyre pressure has changed.
R The wheels or tyres ha vebeen changed or
newly fitted. On-boa
rdcompu ter:
4 Service 5
Tyres #
Swipe down wards on Touch Control on the
left-hand side of thesteering wheel.
The Run Flat Indicator activeRestart message
is shown in the multifunction displa y.
Re start the tyre pressure loss warning sy stem in
th efo llowing situations:
R The tyre pressure has changed.
R The wheels or tyres ha vebeen changed or
newly fitted. #
Tobegin restart, press Touch Control on the
left-hand side of thesteering wheel.
The Tyre pressure now OK? message is
shown in the multifunction displa y. #
Select Yes. #
Toconfirm restart, press Touch Control on
th e left-hand side of thesteering wheel.
The Run Flat Indicator restarted message is
shown in the multifunction displa y. Wheels and tyres
57 9

Af
teryo u ha vedriven for a few minutes, the
tyre pressu reloss warning sy stem monitors
th e set tyre pressures of all the tyres.
Be sure toalso obse rveth efo llowing fur ther
re lated subjects:
R Notes on tyre pressure (/ page571) Wheel
change Note
s on selecting, fitting and replacing
tyres Yo
u can ask for information rega rding permit ted
wheel/tyre combinations at a Mercedes-Benz
Service Cent re. &
WARNING Risk of accident due toincor‐
re ct dimensions of wheels and tyres
If wheels and tyres of the wrong size are
used, the wheel brakes or wheel suspension
components may become damaged. #
Alw aysre place wheels and tyres with
th ose that fulfil the specifications of the
original part. When
replacing wheels, make sure tofit the
cor rect:
R Designation
R Type
When replacing tyres, make sure tofit the
cor rect:
R Designation
R Manufactu rer
R Type &
WARNING Risk of inju rythro ugh exceed‐
ing the specified tyre load-bearing capa‐
city or the permissible speed rating
Exceeding the specified tyre load-bearing
capacity or the permissible speed rating may
lead totyre dama geand tothe tyres bur st‐
ing. #
Therefore, only use tyre types and sizes
appr ovedfo ryo ur vehicle model. #
Obser vethe tyre load-bearing capacity
ra ting and speed rating requ iredfor
yo ur vehicle. *
NO
TEVehicle and tyre damage thro ugh
tyre types and sizes that ha venot been
appr oved Fo
r saf etyre asons, on lyuse tyres, wheels
and accessories which ha vebeen specially
appr ovedby Mercedes-Benz foryo ur vehicle.
These tyres are specially adap tedto the con‐
trol sy stems, such as ABS, ESP ®
and
4MATIC, and mar ked as follo ws:
R MO = Mercedes-Benz Original
R MOE = Mercedes-Benz Original Extended
(run-flat tyres only for cer tain wheels)
R MO1 = Mercedes-Benz Original (only cer‐
tain AMG tyres)
Cer tain characteristics, such as handling,
ve hicle noise emissions, fuel consum ption,
et c. may otherwise be adversely af fected.
Fu rthermore, other tyre sizes could result in 580
Wheels and tyres