check engine MERCEDES-BENZ GLS SUV 2021 User Guide

#
Turn cap 1anti-clockwise and remo veit. #
Top up the engine oil. #
Replace cap 1and turn it clockwise until it
engages. #
Check the oil le vel again (/ page 367). Chec
Chec
king t
king t he coolant lev
he coolant lev el
el &
W
WARNING
ARNING Risk of injury due tomoving
parts
Components in the engine compartment may
continue torun or start unexpectedly even
when the drive system is switched o..
Obser vethefo llowing if you must open the
bonnet: #
Switch o. theve hicle. #
Neverto uch the danger zones sur round-
ing moving components, e.g. thero tation
area of thefa n. #
Remo vejewe llery and watches. #
Keep items of clo thing and hair away
from moving pa rts. &
W
WARNING
ARNING Risk of burns from hot compo-
nent parts in the engine compartment
Cer tain component parts in the engine com-
partment can be very hot, e.g. the engine, the
cooler and parts of theex haust system. #
Allow the engine tocool down and only
to uch component parts described in the
fo llowing. &
W
WARNING
ARNING Risk of scalding from hot cool-
ant
If yo u open the cap, you could be scalded. #
Let the mo tor cool down before opening
th e cap. #
When opening the cap, wear pr otective
glo ves and saf ety glasses. #
Open the cap slo wlytorelease pressure. Maintenance and care
369
369

#
Park theve hicle on a le vel sur face. #
Check the coolant temp erature display in the
inst rument clus ter.
The coolant temp erature must be below 70°C. #
Slowly turn cap 1anti-clockwise torelease
ove rpressure. #
Continue turning cap 1anti-clockwise and
re mo veit. The coolant le
vel is cor rect in thefo llowing cases:
R Ifth e engine is cold, the coolant is up to
mar ker bar 2.
R Ifth e engine is warm,th e coolant is up to
1.5 cm overth e mar ker bar 2. #
If necessar y,top up with coolant that has
been appr ovedfo r Mercedes-Benz.
% Further information on coolant (/ page 432) T
T
opping up t
opping up t he windscr
he windscreen w
een washer syst
asher syst em
em &
W
WARNING
ARNING Risk of burns from hot compo-
nent parts in the engine compartment
Cer tain component parts in the engine com-
partment can be very hot, e.g. the engine, the
cooler and parts of theex haust system. #
Allow the engine tocool down and only
to uch component parts described in the
fo llowing. &
W
WARNING
ARNING ‑ Risk of /re and injury due to
windscreen washer concent rate
Wi ndsc reen washer concent rate is highly 0am-
mable. It could ignite if it comes into contact
with hot engine component parts or the
ex haust system. #
Make sure that no windscreen washer
concent rate spills out next tothe /ller
opening. 370 370
Maintenance and care

Engine
Engine
Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
To switch off the engine,
press the Start/Stop but-
ton for at least 3 seconds
or 3 times. *Y
ou ha vepressed the start/s top button while theve hicle is in motion. #
Information about switching o. theve hicle while driving (/ page 191).
Cannot start engine See
Owner's Manual *T
hevehicle cann otbe star ted. #
Switch theve hicle o. and switch it back on #
Ifth e display message still appears, consult a quali/ed specialist workshop.
+
Top up coolant See Own-
er’s Manual *T
he coolant le vel is too lo w.
* N NO
OTE
TE Engine damage due toinsu1cient coolant #
Avoid long journe yswith insu1cient coolant. #
Add coolant (/ page 369). #
Have the engine cooling system checked at a quali/ed specialist workshop. Displ
aymessages and warning/indicator lamps
461
461

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions #
Switch o. theve hicle. #
Add 1 l of engine oil (/ page 368). #
Check the engine oil le vel.
No tes on engine oil (/ page 430).
5
Engine oil pressure Stop
Switch off engine *T
he oil pressure is too lo w.
* N
N O OTE
TE Engine damage caused bydriving with insu1cient oil pressure #
Avoid driving with insu1cient oil pressure. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Switch o. theve hicle. #
Consult a quali/ed specialist workshop.
5
Engine oil level cannot be
measured *T
he elect rical connection tothe oil le vel sensor has been inter rupted or the oil le vel sensor is faulty. #
Consult a quali/ed speciali stwo rkshop. Displ
aymessages and warning/indicator lamps
503 503

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions #
Notethe messages on the instrument displa y.
If t
If t he coolant t
he coolant t em
emper
per atur
atur e displa
e displa y is at t
y is at the low
he lower end of t
er end of t he t
he tem
emper
per atur
atur e scale:
e scale: #
Consult a quali/ed specialist workshop.
If t
If t he coolant t
he coolant t em
emper
per atur
atur e displa
e displa y is at t
y is at the upper end of t
he upper end of t he t
he tem
emper
per atur
atur e scale:
e scale: #
Exit theve hicle and keep a safe distance from it until the engine has cooled down. #
Check the coolant le vel (/ page 369). #
Make sure that the air supply tothera diator is not obstructed. #
Avoiding high loads on the engine, drive tothe nearest quali/ed specialist workshop. In doing so, ensu rethat the
coolant temp erature display remains below 120°C.
ÿ
Coolant warning lamp (yel-
low) *T
he yellow coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The charge air, transmission oil or battery cooling is faulty
R The radiator shutters are bloc ked or defective #
Avoiding high loads on the engine, drive tothe nearest quali/ed specialist workshop. Displ
aymessages and warning/indicator lamps
509
509

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
;
Engine diagnosis warning
lamp *T
he yellow engine diagnostics warning lamp is lit while the engine is running.
A malfunction has occur red in the engine, theex haust system or the fuel system.
The emissions limit value may ha vebeen exceeded and the engine may be running in eme rgency operation mode. #
Have theve hicle checked as soon as possible at a quali/ed specialist workshop.
V
V ehicles wit
ehicles wit h a diesel engine:
h a diesel engine: the fuel tank may ha vebeen run dr y. #
Start the engine thre eto four times aTer refuelling.
If th eye llow engine diagnosis warning lamp goes out, emer gency ope ration mode is cancelled. The vehicle need not
be checked.
p Engine operating temp era-
ture warning lamp *V
Vehicles wit
ehicles wit h a pe
h a petr
trol engine:
ol engine: aTer a cold start, the blue engine operating temp erature warning lamp is on.
Engine output and engine torque arereduced. #
Take this into consideration in your driving style.
#
Electrical fault warning lamp *T
hered electrical fault warning lamp is lit.
There is a fault in the electrics. #
Notethe messages on the instrument displa y.510
510
Display message
s andwarning/indicator lamps

5
Add 1 litre engine oil when next
re fuelling ............................................... 502
é ATTENTION ASSIST inoperati ve..... 471
é ATTENTION ASSIS T:Take a
break!.................................................... 471
: Automatic driving lights inoper-
ative...................................................... 448
_ Cannot fold 2nd seat row for-
wa rds See Owner's Manual .................... 460
Á Change key batteries .................... 446
J Check brake 0uid le vel.................. 470
ï Check trailer hitch lock (white
display message) .................................... 453
h Check tyre(s) ................................ 496
! Clean the fuel /lter....................... 463
Á Compressor is cooling .................. 486
ÿ Coolant Stop vehicle Switch
engine o............................................... 462
! currently una vailable See Own-
er's Manual............................................4 87÷
currently una vailable See Own-
er's Manual............................................4 88
5 Engine oil le vel cannot be meas-
ured....................................................... 503
5 Engine oil le velRe duce oil le vel..... 502
5 Engine oil le velSt op vehicle
Switch engine o.................................... 502
5 Engine oil pressure Stop Switch
o. engine.............................................. 503
ä Fault Drive at max. 80 km/h
...................................................... 483, 484
ä Fault Stop.................................... .484
6 Front leT malfunction Consult
wo rkshop (e xample)...............................4 43
& inoperative Battery low................. 451
& inoperative Refuel vehicle............. .451
& inoperative See Owner's Man........ 451
! inoperative See Owner's Manual.. .488
÷ inoperative See Owner's Manual.. .489
T inoperative See Owner's Manual.. .490 G
Inoperative................................... 491
î inoperative....................................4 75
: Intelligent Light System inopera-
tive........................................................ 449
Á Key being initialised Please wait.... 447
Á Key not de tected (red display
message).............................................. .447
Á Key not de tected (white display
message).............................................. .446
: LeT dipped beam (e xample).......... 448
6 LeT windowbag malfunction
Consult workshop (e xample).................. 443
 Lowe ring....................................... 485
: Malfunction See Owner's Man-
ual ......................................................... 448
î Max. speed 40 km/h .................... 476
ð Maximum speed exceeded ............ 475
î Not possible in cur rent drive
prog ram................................................. 475
Ø .................................................... 499 Index
527 527

Ac
tive Brake Assist Functions limi ted
See Owner's Manual.............................. 491
Ac tive Distance Assist available again ..... 474
Ac tive Distance Assist cur rently
una vailable See Owner's Manual ............ 473
Ac tive Distance Assist inoperative.......... 474
Ac tive Lane Keeping Assist cur rently
una vailable See Owner's Manual ............ 480
Ac tive Lane Keeping Assist inoperative... 480
Ac tive Steering Assist cur rently
una vailable due tomultiple emer-
ge ncy stops........................................... 476
Ac tive Steering Assist cur rently
una vailable See Owner's Manual ............ 476
Ac tive Steering Assist inoperative...........4 76
Ac tive Stop-and-Go Assist cur rently
una vailable see Owner's Manual .............477
Ac tive Stop-and-Go Assist inoperative
See Owner's Manual.............................. 477 Ad
aptive Highbeam Assist Plus cur-
re ntly una vailable See Owner's Manual ... 450
Ad aptive Highbeam Assist Plus inop-
erative.................................................. .450
Anti-theT alarm system Malfunction ....... 460
Apply brake todeselect Park (P) posi-
tion....................................................... .464
Apply brake toselect D or R ...................464
Apply brake toselect R .......................... 464
Au xiliary battery malfunction (red dis-
play message) ....................................... .466
Au xiliary battery malfunction (white
displ aymessage) .................................... 466
Beginning emer gency stop..................... 477
Blind Spot Assist cur rently una vailable
See Owner's Manual.............................. 478
Blind Spot Assist inoperative.................. 479
Blind Spot Assist not available when
to wing a trailer See Owner's Manual ...... 479Cann
otstart engine See Owner's
Manual.......................................... 461, 495
Check brake pads See Owner's Man-
ual......................................................... 470
Cruise control and Limi ter inoperative.... 472
Cruise control inoperative......................4 72
Cruise control o.................................... 472
Device de tected at diagnostics con-
nection See Owner's Manual................. .492
Drive system Malfunction Stop Switch
engine o............................................... 463
Drive system Malfunction Visit work-
shop ...................................................... 463
Fr ont-passenger airbag disabled See
Owner's Manual .................................... .444
Fr ont-passenger airbag enabled See
Owner's Manual .................................... .444
Gearbox pr otection Limit 30 km/h
Switch o. LOW RANGE.......................... 459
Hazard warning lamps malfunctioning .... 450 Index
529 529

Emerg
Emerg
ency call
ency call
see Mercedes-Benz emer gency call system
Eme rg
Emerg encykey
ency key
Inserting/ removing.................................. 83
Locking/unlocking the door s................... 88
Unlocking theta ilgate.............................. 95
Emerg
Emerg ency oper
ency oper ation mode
ation mode
St arting theve hicle............................... .192
Emerg
Emerg ency r
ency release
elease
Ta ilgate.................................................... 95
Emerg
Emerg ency spar
ency spar e wheel
e wheel
In0ating.................................................4 15
No tes..................................................... 414
Engine
Engine Engine number....................................... 423
Starting (emer gency ope ration mode ).... 192
St arting (Remo teOnline)........................ 193
Engine data
Engine data
Displaying............................................. .207
Engine electr
Engine electr onics
onics
No tes..................................................... 420
Engine number Engine number............................................. 423 Engine oil
Engine oil
Additives................................................ 430
Capacity................................................ 431
Checking the oil le vel using the on-
board computer.....................................3 67
MB-F reigabe or MB-Appr oval................. .431
Quality................................................... 431
To pping up............................................ .368
Ent Ent er
ering/e
ing/e xiting lev
xiting lev el
el
Setting................................................... 272
ERA
ERA -GL
-GLON
ONASS tASS t es
est modet mode
St arting/ending.................................... .354
Err
Err or message
or message
see Display message
ESC (Electr
ESC (Electr onicSt
onic Stability Contr
ability Contr ol)
ol)
see ESP ®
(Elect ronic Stability Prog ram)
ESP
ESP ®
®
Crosswind Assis t.................................... 233
Tr ailer stabilisatio n................................. 233
ESP
ESP ®
®
(Electr
(Electronic St
onic Stability Pr
ability Pr ogr
ogram)
am)
Ac tivating/deactivating.......................... 234
Fu nction/no tes...................................... 232
EU type approv
EU type appr oval number
al number ............................. 423 Ext
Ext
endable r
endable r unning boar
unning boar ds
ds ............................. 89
Ext
Ext endable st
endable st ep
ep
see Running boa rds
Ext
Ext er
erior lighting
ior lighting
Car e...................................................... 376
Ext
Ext er
erior lighting
ior lighting
see Lights F
F
F
F atigue det
atigue det ection
ection
see ATTENTION ASSIST
F
F ir
ir e e
e e xtinguisher
xtinguisher.......................................... 381
F
F irs
irst-aid kit t-aid kit (soT
(soTsided)
sided)................................. 381
Flacon
Flacon Inserting/removing................................ 182
Flat to
Flat towing
wing
see Tow- bar system
Flat tyre
Flat tyre MOExtended tyres................................. 382
Notes..................................................... 382
TIREFIT kit.............................................. 384
Wheel chang e........................................ 409
Floor mats
Floor mats................................................... 158 Index
533 533