trailer MERCEDES-BENZ GLS 2020 Service Manual

to
wing eye. Fasten theto w bar tothetrailer
hitc h.
% Mak esur eth at cover1 eng ages inthe
bum perwhen youre mo vetheto wing eye.
* NO
TEDama getotheve hicle dueto
inc orrect useof theto wing eye When
ato wing eyeis used toreco vera ve hi‐
cle, theve hicle maybe damag edinthepr oc‐
ess. #
Onlyuse theto wing eyeto tow aw ay or
to w star tth eve hicle. To
w star ting theve hicl e(eme rgency engine
st ar t) Ve
hicl eswith automatic transmiss ion
* NO
TEDama getotheaut omatic trans‐
mission duetotow star tin g The
automat ictransm issionma ybe damag ed
in thepr ocess oftow star tin gve hicles with
aut omatic transmission. #
Vehicles withaut omatic transmission
mus tno tbe tow star ted. #
Vehicles withaut omatic transmission must
no tbe tow- star ted. Electr
icalfuses No
teson electr icalfuses &
WARNIN GRisk ofacci dent andinjury
due tooverloaded lines
If yo uman ipulat eor bridg eafa ulty fuse orif
yo ure place itwit hafuse withahigher
am per age, theelectr icline could beove rloa‐
ded.
This could result inafire . #
Alw aysre place faulty fuseswit hspec i‐
fi ed newfuses containin gth ecor rect
am per age. *
NO
TEDama gedue toinc orrect fus es Electr
icalcom pone ntsorsystems maybe
damag edbyinc orrect fus es, ortheir func ‐
tion ality maybe signif icantlyim pair ed. #
Onlyuse fuses that have been approved
by Mer cedes-Ben zand whic hha ve the
cor rect fus era ting . Blo
wn fuse smu stbe replaced withfuses ofthe
same rating ,wh ich yo ucan recogni zeby the
colo rand fusera ting .The fuse rating sand fur‐
th er information tobe obser vedcan befound in
th efuse assignmen tdiagr am.
Fu se assignment diagram: onthefuse boxin
th ecar gocom partmen t(/ page51 2).
* NO
TEDama geormalfunct ionscaused
by mois ture Mois
turema ycause damagetotheelectr ical
sy stem orcause itto malfu nction. 51
0
Brea kdo wnassista nce

R
Impai reddr iving comfort
R Suscep tibilitytodamag e &
WARNIN GRisk ofacci dent caused by
re peat eddrop intirepr essur e
If th etir epr essur edr ops repeat edly,th e
wheel, valve or tirema ybe damag ed.
Ins ufficie nttirepr ess urecan causethetir es
to bur st. #
Inspect thetir efo rsigns offore ign
obje cts. #
Chec kwhe ther thewheel orvalve has a
leak . #
Ifyo uar eunab leto rectify thedamag e,
con tact aqu alif ied spec ialistwo rkshop. Yo
ucan find informa tionon tirepr ess ures for
th eve hicle's fact or y-ins talled tires on thefo llo w‐
ing labels:
R Tire and Loadi ngInfo rm atio nplacar don the
B‑pil larof your vehicle (/page522).
R Tire pressur eta ble ontheinside ofthefuel
fi ller flap (/ page51 6). Ob
serveth emaximum tirepr essur e
(/ page528).
Use asuit able pressur ega ug eto checkth etir e
pr essur e.The outerappear anceofatir edoes
no tper mit anyre liable conclusion aboutthetir e
pr essur e.
Ve hicl eswith atir epr ess uremonit oring sys‐
te m: Youcan also checkth etir epr essur eusing
th eon- boar dcom puter.
Onl ycor rect tirepr ess ures whenth etir es are
cold. Condition sfo rcold tires:
R The vehicle hasbeen parkedwit hth etir es
out ofdir ect sunlight forat lea stthre ehour s.
R The vehicle hastrave led less than 1mile
(1 .6 km ).
A rise inthetir ete mp eratur eof 18 °F(10 °C)
incr eases thetir epr essur eby appr ox.10 kPa
(0. 1ba r/1 .5psi ).Ta ke this int oacc ount when
ch ecking thetir epr essur eof wa rm tires.
The tirepr es su re recomme ndedforincr ease d
loa d/spee din thetir epr essur eta ble can affect
th eride comf ort. &
WARNIN GRisk ofacci dent dueto
uns uitable accessories ontireva lve
If yo umoun tuns uitable accessories onto tire
va lves, thetir eva lves ma ybe ove rloaded and
malfunct ion,whic hcan cause aloss oftire
pr essur e.Afterm arke ttir epr es su re monit or‐
ing systems willcause thetir eva lve to
re main open, depending onthedesign. This
can also result inaloss oftirepr essur e. #
Onlyscr ew standar dva lve caps orvalve
cap sspe cifica llyapprove dby
Mer cedes-Ben zfo ryo ur vehicle onto
th etir eva lve. No
teson trailer operation
Alw aysinf lateth ere ar axle tires tothere com‐
mend edtirepr ess ures on thetir epr essur eta ble
fo rincr ease dloa d. Ti
re pres sur etab le The
tirepr ess ureta ble ison theinside ofthe
fuel filler flap. 51
6
Wheels andtires

R
Recomme ndedtirepr ess ures 1 forcold
tir es. The recomme ndedtirepr ess ures are
va lid forth emaximum permissible loadand
up tothemaximum permissible vehicle
speed.
Please alsonote:
R Information onper missib lewe ight sand loads
on theve hicle identif ication plate
(/ page552).
R Information ontirepr essur ein thetir epr es‐
sur eta ble (/ page51 6).
Fu rther relat ed subje cts:
R Determ inin gth emaximum permissible load
(/ page523)
R Noteson tirepr essur e(/ page51 5). Ste
psforDe term ining Correct Load Limit The
follo wing steps have been developed as
re qu ired ofall manuf acturersunder Title 49,
Co de ofU.S. Feder alRe gulations, Part57 5, pur‐
sua nttothe"N ational Traf fic and MotorVe hicle
Saf etyAc tof 1966". #
(1):Locat eth est at emen t"The combined
we ight ofocc upant sand cargoshould never
exc eed XXX kgorXXX lbs." onyour vehicle's
placar d. #
(2): Determ ine thecombin edweight ofthe
dr iver and passeng ersth at will beriding in
yo ur vehicle. #
(3): Subtr actthecombin edweight ofthe
dr iver and passeng ersfrom XXX kgor
XXX lbs. #
(4): The resulting figur eeq uals theav ailable
amoun tof car goand luggageload capac ity.
Fo rex am ple, ifth e"XXX" amount equals
14 00 lbs. and ther ewill befive 150lb pas ‐
seng ersin your vehicle, theamount ofavaila‐
ble cargoand luggageload capac ityis
65 0lbs. (140 0-75 0(5 x15 0) =650 lbs.) #
(5):De term ine thecombin edweight oflug‐
ga ge and cargobein gloaded ontheve hicle.
The weight mayno tsaf elyexc eed theav aila‐
ble cargoand luggageload capac itycalc ula‐
te din Step 4. #
(6): Ifyo ur vehicle willbetowing atrailer ,
load from your trailer willbetrans ferred to yo
ur vehicle. Consult this manual todeter‐
mine howthis reduces theav ailable cargo
and luggageload capac ityofyour vehicle.
% Notall vehicles areper mitt edtotow a
trailer .To wing atrailer isonl yper mittedifa
tra iler -hit chisins talled. Please consult an
aut hor ized Mercedes -Benz dealer ifyo uha ve
an yqu estion sabout towing atrailer with
yo ur vehicle.
Ev en ifyo uha ve cal cul ated thetot alload care‐
full y,yo usho uld still mak esur eth at themaxi‐
mum permissible gross weight andthemaxi‐
mum gross axle weight rating ofyour vehicle are
no texc eeded. Details can befound ontheve hi‐
cle identif ication plate. #
Have your loaded vehicle –including driver ,
occupants andload –we ighed onave hicle
we ighbr idge.
The measur edvalues mayno texc eed the
maximu mper missi blevalues stat ed on the
ve hicle identif ication plate.
Fu rther relat ed subje cts:
R Calculation exam ple forde term inin gth emax‐
imum load(/page52 4) Wheels
andtires 523

Un
ifor m Tire Quality Grading Standar ds:a
unif orm standar dto grade thequ alit yof tires
wit hre ga rd totrea dqu alit y,tiretracti onand
te mp eratur ech aract eristic s.The qualit ygr adin g
asses smentismade bythemanuf acturerfollo w‐
ing spec ificat ions from theU. S. government. The
qu alit ygr ade ofatir eis im print ed on theside
wa llof thetir e.
Re comm endedtir epr essu re:th ere comme n‐
ded tirepr ess ureis thetir epr essur especif ied
fo rth etir es mount edtotheve hicle atthefa c‐
to ry.
The tireand information table con tains there c‐
omme ndedtirepr ess ures forcold tires, themax‐
imum permissible loadandthemaximum per‐
missible vehicle speed.
The tirepr essur eta ble con tains there comme n‐
ded tirepr ess ures forcold tires under various
oper ating condit ions,i.e.loading and/orspeed
of theve hicle.
Incr eased vehicl ewe ight duetooptiona l
eq uip ment :th ecombin edweight ofall standar d
and optio nal equipme ntavailable forth eve hicle, re
ga rdless ofwhe ther itis actually installed on
th eve hicle ornot.
Rim: thepar tof thewheel onwhic hth etir eis
ins talled.
GA WR (Gross AxleWe ight Ratin g):th eGA WR
is themaximum permissible axleload. The
actual loadonanaxle mustne verexc eed the
gr os saxle weight rating .The gross axlewe ight
ra ting canbefound ontheve hicle identif ication
plat eon theB‑pillar onthedr iver's side.
Speed ratin g:thespeed rating ispa rtof thetir e
identif ication .It specif iesthespeed rang efo r
whic hatir eis appr oved.
GV W(Gr oss Vehicl eWe ight ):th egr oss vehicle
we ight comprises thewe ight oftheve hicle
including fuel,tools, thespar ewheel, accesso‐
ri es installed, occupant s,lugg ageand thetrailer
dr aw bar nose weight ,if applicable. Thegros s
ve hicle weight mustno texc eed thegr oss vehicle
we ight rating GVWR asspecif iedontheve hicle
identif ication plateon theB‑pillar onthedr iver's
side.
GV WR (Gross Vehicl eWe ight Ratin g):th e
GV WR isthemaximum permitt edgross weight of
thefully laden vehicle (weight oftheve hicle
including allaccessor ies,occupants, fuel,lug‐
ga ge and thetrailer draw bar nose weight ifappli‐
cable). Thegros sve hicle weight rating issp eci ‐
fi ed on theve hicle identif ication plateon the
B‑pil laron thedr iver's side.
Maxim umweight ofthelad envehicl e:the
maximu mwe ight isthesum ofthecurb weight
of theve hicle, thewe ight oftheaccessor ies,the
maximu mloa dand thewe ight ofoption aleq uip‐
men tins talled atthefa ct or y.
Kilop ascal(kP a):metric unit fortir epr essu re.
6.9 kPacor responds to1psi .Ano ther unit for
tir epr es su re isbar .10 0kilop ascal(kP a)equals
1 bar .
Lo ad inde x:inadd ition totheload-bear ing
inde x,theload indexma yalso beimprint ed on
th eside wallof thetir e. This specif iestheload-
bear ingcapacity ofthetir emor epr ecisel y.
Cur bwe ight :th ewe ight ofave hicle withstand‐
ar deq uipme ntinc ludin gth emaximum capacity
of fuel, oiland coolant .It also includes theair
con ditionin gsy stem and option aleq uipment if 532
Wheels andtires

All
mod els(vehi‐
cles withAMG
St yling) 1 1
Front 2 2
Rear
Of f-road leve l22 5° 24°
Of f-road leve l32 7°-28° 25°-26° Mer
cedes‑Ma y‐
bac h 1 1
Front 2 2
Rear
Nor mal leve l2 4°21°
Ra ised leve l2 7°25° *Depend
ingonthetir esize.
Maxim umgradien tcli mbing ability
The vehicle's gradient climbing abilitydepends
on thewe ight distribution intheve hicle, thete r‐
ra in con dition sand thero ad sur face condi tions.
The specified va lue applies when:
R The vehicle isready todrive
R The LOWRAN GEoff-r oad gear ofthetra ns‐
fe rcase iseng aged R
The road sur faces condi tions andthus the
tr acti onarego od
A grad ient climbi ngability of100% corresponds
to an incline of45 °.
Obse rveth eno teson driving inmount ainous ter‐
ra in . Model
Maximumgra‐
dien tcli mbing
abil ity
Ve hicl eswithout Off-
ro ad pac kage 80%
Ve hicl eswith Off-road
pac kage
When LOWRANGE off-
ro ad gear iseng aged 10
0% Mer
cedes‑Ma ybachM aximumgra‐
dien tcli mbing
abil ity
All mode ls 80% Tr
aile rhitc h Gene
ralno teson thetrailer hitch Modif
ications totheengine cooling system may
be neces sary,dependin gon theve hicle model.
The retrof itti ng ofatrai le rhi tc his only perm issi‐
ble ifato wing capac ityisspec ified inyour vehi‐
cle documents.
Fu rther information canbeobt ained ataqu ali‐
fi ed specialis two rkshop. To
wing capacit y The
tongu ewe ight isno tinc luded intheto wing
capac ity. Mod
el Towing capacit y,
br ak ed
All models 7716 .2 lbs(3 500 kg) Mer
cede s‑Maybac hT owing capa city,
br ak ed
All models 7716 .2 lbs(3 500 kg) Te
ch nica lda ta 565

Maximum
tongue weight *
NO
TEDama gecau sed bythetrailer
comin gloose If
th eto ngu ewe ight used istoolow, the
tr ai le rma ycome loose . #
The tongu ewe ight mustno tbe belo w
11 0.2 lb(50 kg). #
Use ato ngu ewe ight that isas clo seas
poss ibletothemaximum permissible
to ngu ewe ight . To
ngue weight Model
Maximumtongue
we ight
All models 617.3 lbs (280 kg) Mer
cede s‑Maybac hM aximum tongue
we ight
All models 617.3 lbs (280 kg) Pe
rm issible rear axle load (traile roper ation ) Miss
ingvalues werenotav ailable atthetime of
going topress.
Axle load Model
Axleload
All models 4078 .5 lbs(1 850 kg) Mer
cede s‑Maybac hA xleload
All models 566
Tech nica lda ta

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
00C5 Lowering *T
hevehicle leve lma ybe lowe redfo rth efo llo wing reason s:
R Youha ve select edadif fere nt drive pr ogr am.
R Youha ve exceed edthespeed limit.
R Youha ve chang edtheve hicle leve lby pressing thebutt on.
R Oper ation withatrailer orbicy clerack :if an elect rical connecti onhasbee ncor rectl ymad e,youha ve excee‐
ded thespeed limit.
R Youha ve switc hedonthere ar foglam pin theof f-r oad leve l+3.
00C4
Vehic leRising *Y
our vehicle isadjus tingtotheleve lyo uha ve select ed.
ä Malfunction DriveatMax.
50 mph *A
tle as tone mainfunctio nof theE- AC TIVE BODY CONTR OLsystem ismalfunct ioning.
The system isdeactiv ated.
* NO
TEThe vehicle's suspension anddam ping behaviorhaschang edsign ifican tly, theve hicle body maytilt
hea vilyto theside during corner ing. #
Reduce vehicle speed. Drive on car efull y. #
Reduce theve hicle speed consider ablybef oreta king acur ve. 59
4
Displa ymessag esand warning/ indic ator lam ps

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions #
Avoid sudden steer ing movements. #
Continue driving careful lyat max imum 50mph(80 km/h). #
Ifpossible, stop theve hicle when safeto do sointhetra ffic con dition sand switc hth eignition offand onagain. #
Ifth edispla ymessag econ tinues tobe displa yed, con sult aqu alif ied spec ialistwo rkshop.
ä Malfunction Stop *T
her eis aser ious malfunction affecting thehy draulics oftheE- AC TIVE BODY CONT ROLsy stem.
The system isdeactiv ated.
* NO
TEThe vehicle's driving charact eristic sha ve chang edsign ifican tly. #
Pull overand stop theve hicle safely assoon aspossible inaccor dance withth etra ffic con dition s.Do not
con tinue drivin gunder anycir cums tances. #
Stop theve hicle immediat elyinaccor dance withth etraf fic condi tions.Do notcontinu edr ivi ng und eranycir‐
cums tances. #
Consu ltaqu alif ied spec ialistwo rkshop.
Drive MoreSlowly *Y
ouaredr iving toofast forth eselect edvehicle leve l. #
Drive mor eslo wlyand then select thedesir edvehicle leve lag ain.
Yo uar edr ivin gto oqu ickl ywit hatrailer orthetrailer hitchsoc ketis be ing used ,e.g .fo ra re ar cycle rack . #
Read theinf ormation ontrailer operation. Displa
ymessag esand warning/ indic ator lam ps 595

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions #
Ifth edispla ymessag edoes notdisappear ,st op theve hicle inaccor dance withth etra ffic con dition sand restar t
th eengine.
Blind SpotAssist Inopera-
tive *B
lind SpotAss istis malfun ctionin g. #
Consult aqu alif ied spec ialistwo rkshop.
Blind SpotAssist NotAvail-
able When Towing aTrailer
See Operator's Manual *W
hen youes tablish theelectr icalconnect iontothetra iler ,Blind SpotAssis tis una vailable. #
Press thelef t-hand Touc hCon trol and ackn ow ledg eth edispla ymessag e.
Act ive Blind SpotAssist
Current lyUnavailable See
Operator 'sManual *A
ctiv eBli nd Spo tAssi stistemp orarily una vailable.
The system limits have been reac hed (/page29 1). #
Drive on .
On ce thecause ofthepr oblem isno long erpresent ,th esy stem will beavailable again.
or #
Ifth edispla ymessag edoes notdisappear ,st op theve hicle inaccor dance withth etra ffic con dition sand restar t
th eengine.
Act ive Blind SpotAssist
Inoper ative *A
ctiveBli nd Spo tAssi stismalfun ctionin g. #
Consult aqu alif ied spec ialistwo rkshop. Displa
ymessag esand warning/ indic ator lam ps 599

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
Act ive Blind SpotAsst.Not
Available WhenTowing a
Trailer SeeOperator' sMan-
ual *W
hen youes tablish theelectr icalconnect iontothetra iler ,Ac tiveBli nd Spo tAssi stisuna vailable. #
Press thelef t-hand Touc hCon trol and ackn ow ledg eth edispla ymessag e.
Act ive Parkin gAssist and
PARKTRONIC Inoperative
See Operator 'sManual *A
ctivePa rking Assistand Parking AssistPA RK TRONI Caremalf unction ing . #
Stop theve hicle inaccor dance withth etra ffic con dition sand restar tth eengine. #
Ifth edispla ymessag econ tinues tobe displa yed, con sult aqu alif ied spec ialistwo rkshop.
Traffic SignAssist Cur-
rently Unavaila bleSee
Operator's Manual *T
raffic Sign Assistis temp orarily una vailable. #
Drive on.
Onc eth ecause ofthepr oblem isno long erpresent ,th esy stem will beavailable again.
Traf ficSig nAs sist Inoper a-
tiv e *T
raffic Sign Assistis malfun ctionin g. #
Stop theve hicle inaccor dance withth etra ffic con dition sand restar tth eengine. #
Ifth edispla ymessag econ tinues tobe displa yed, con sult aqu alif ied spec ialistwo rkshop. 600
Displa ymessag esand warning/ indic ator lam ps