fuel pressure MERCEDES-BENZ C-CLASS CABRIOLET 2021 User Guide

#
Adjust the tyre pressure where neces‐
sar 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 due torepea‐
te d pressure drop in the tyres
The wheels, valves or tyres could be dam‐
aged.
To o low a tyre pressure can lead tothe tyres
bur sting. #
Examine the tyres forfo re ign objects. #
Check whe ther the tyre has a puncture
or theva lve has a leak. #
Ifyo u are unable torectify the damage,
conta ct aqualified specialist workshop. Information on
there commended tyre pressure
fo rth eve hicle's factor y-fitted tyres can be found on
the tyre pressure table on the inside of the
fuel filler flap (/ page 397).
Use a suitable pressure gauge tocheck the tyre
pressure. The outer appearance of a tyre does
not permit any reliable conclusion about the tyre
pressure.
Only cor rect tyre pressures when the tyres are
cold. Conditions for cold tyres:
R The vehicle has been par ked with the tyres
out of direct sunlight for at least thre e hours.
R The vehicle has tr avelled less than 1.6 km.
The vehicle's tyres heat up when driving. As the
te mp erature of the tyres increases, so too does
th e tyre pressure.
Ve hicles with a tyre pressure monitoring sys‐
te m: you can also check the tyre pressure using
th e on-board computer.
Note s on trailer operation
Alw ays inflate there ar axle tyres tothere com‐
mended tyre pressures on the tyre pressure
ta ble for increased load. Ty
re pressure table The tyre pressure
table is on the inside of the
fuel filler flap. If one or more tyre sizes precede a tyre pres‐
sure, thefo llowing tyre pressure information is
only valid forth ose tyre sizes and their respec‐
tive load condition. Wheels and tyres
397

If
th e preceding tyre sizes are complemented by
th e+ symbol, the tyre pressure information
fo llowing sho wsalternative tyre pressures. Fuel
consum ption may then increase slightl y.
The load conditions "partially laden" and "fully
laden" are defined in theta ble for dif fere nt num‐
be rs of passengers and amounts of luggage. The
actual number of seats may dif fer from this. 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.
The tyre pressure and the tyre temp erature
appear in the on-board computer (/ page 398).
If th ere is a subs tantial pressure loss or if the
tyre temp erature is excessive, you will be
wa rned with display messages (/ page475) or
th eh warning lamp in the instrument clus ter
( / page 498). The tyre pressure monitoring 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.
In most cases, the tyre pressure monitoring sys‐
te m will auto matically update 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 (/ page 399).
Sy stem limits
The sy stem may be impaired or may not function
particularly in thefo llowing situations:
R the tyre pressure has been set incor rectly
R sudden pressure loss caused byafo re ign
object penetrating the tyre, forex ample
R there is a malfunction caused byano ther
ra dio signal source
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: 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‐ 398
Wheels and tyres

Instrument display (standard)
Wi
descreen co ckpit instrument displ ay Depending on
the display setting, the positions
of the indicator lamps on the instrument display
may dif fer from theex ample shown.
Indicator and warning lamps:
6 Re
stra int sy stem (/ page 487)
ü Seat belt (/
page 487)
ï Trailer hit ch (/page 488)
Ù Powe rst eering (/ page 488)
ÿ Coolanttemp erature (/ page 489)
; Engine diagnostics (/
page 489)
% Ve
hicles with a diesel engine: pre‐
gl ow
# Electrical
fault (/ page 489)
8 Re
ser vefuel with fuel filler flap loca‐
tion indicator (/ page 489)
! Elect
ric pa rking brake (red)
(/ page 492)
! Electric parking brake (yellow)
(/
page 492)
J Brakes (yellow) (/
page 492)
J Brakes (red) (/
page 492) L
Distance warning (/ page 494)
ä AIRMATIC (/ page 494)
ä DYNA MIC BODY CONTROL
(/ page 494)
! ABS (/
page 495)
÷ ESP®
(/ page 495)
å ESP®
OFF (/ page 495)
h Ty
re pressure monitoring sy stem
(/ page 498)
T St
anding lights (/ page119)
L Low beam (/
page119)
K High beam (/
page121)
#! Tu
rn signal lights (/ page121)
R Re
ar fog light (/ page119) 486
Displaymessa ges and warning/indicator lamps

5
Engine oil le velRe duce oil le vel.... 484
5 Engine oil le velSt op vehicle
Switch engine off.................................. 484
5 Engine oil pressure Stop
Switch off engine.................................. 485
ä Fault Drive at max. 80 km/h........ 464
6 Front left malfunction Consult
wo rkshop (e xample).............................. 431
_ Front left seat backrest not
loc ked (e xamp le).................................. .445
! inoperative See Owner's Man‐
ual......................................................... 468
÷ inoperative See Owner's Man‐
ual......................................................... 469
T inoperative See Owner's Man‐
ual......................................................... 470
G Inoperative................................... 472
: Intellige nt Light Sy stem inoper‐
ative...................................................... 439 Á
Key not de tected (red displ ay
messa ge)............................................... 435
Á Key not de tected (white displ ay
messa ge)............................................... 434
: Left dipped beam (e xamp le)........ .438
6 Left wind owbag malfunction
Consult workshop (e xample)................ .431
¢ Lowe ring...................................... 465
: Malfunction See Owner's Man‐
ual......................................................... 438
ð Maximum speed exceeded ........... 459
Ø ..................................................... 480
ç Off................................................4 58
ë Off................................................ 456
K Open/close top comple tely.......... 437
! Parking brake See Owner's
Manual .................................................. .451
É Please reduce speed .................... 466
Ý Please wait 48 V battery charg‐
ing ........................................................ .474 _
Rear left seat backrest not
loc ked (Example)................................... 445
h Rectify tyre pressure.................... 477
Ø Refill Ad Blue See Owne r’s
Manual.................................................. 480
! Release parking brake .................. 454
¸ Replace air cleaner ......................448
Á Replace key.................................. 434
8 Reser vefuel le vel......................... 448
6 Restra int sys. malfunction Con‐
sult workshop........................................ 431
# See Owner's Manual....................4 73
Ù Steering malfunction Incre ased
ph ysical ef fort See Owner's Manual ......443
Ù Steering malfunction Stop
immediately See Owner's Manual .........443
# Stop vehicle Lea veengine run‐
ning ........................................................ 474
# Stop vehicle See Owner's Man‐
ual......................................................... 47351 0
Index

Wa
rning triangle
Re moving............................................... 372
Setting up.............................................. 373
Wa rning/indicator lamp
! ABSwarning lamp....................... .495
J Brake sy stem warning lamp
(red)...................................................... 493
J Brake sy stem warning lamp
(yellow).................................................. 493
ÿ Coolant warning lamp................. .489
! Electric parking brake indicator
lamp (red).............................................. 492
# Electrical fault warning lamp....... .491
; Engine diagnosis warning lamp... .491
å ESP®
OFF warning lamp.............. .497
÷ ESP®
wa rning lamp..................... .496
8 Fuelreser ve wa rning lamp
lights up................................................ 492
Ù Powe rst eering warning lamp
(red)...................................................... 488 6
Restra int sy stem warning lamp... .487
ü Seat belt warning lamp................ 487
ä Suspension warning lamp (yel‐
low)....................................................... 495
! The elect ric pa rking brake (yel‐
low) indicator lamp............................... .492
ï Trailer tow hit chwarning lam p..... 489
h Tyre pressure monitoring sys‐
te m wa rning lamp................................. .498
L Warning lamp for dis tance
wa rning function................................... .494
Overview............................................... 485
Wa rning/indicator lamps
PA SSENGER AIR BAG.............................. 49
Wa rranty ...................................................... 32
Wa sher fluid
see Windsc reen washer fluid
Wa shing byhand (care)............................ 364
Wa ter tank
see Air-water duct We
ather information ................................. 295
What3words Destination entry with a 3 word
address................................................. 275
Wheel change
Fitting a new wheel............................... 408
Lo we ring theve hicle.............................4 09
Prepa ration.......................................... .405
Ra ising theve hicle................................4 06
Re moving a wheel................................. 408
Re moving/fitting hub caps................... .405
Wheel change
see Emergency spa rewheel
Wheel rotation .......................................... .403
Wheels Care ...................................................... 368
Checking............................................... 395
Checking the tyre pressure (tyre
pressure monitoring sy stem)................. 398
Fitting.................................................... 408
Flat tyre.................................................3 74
Inter changing....................................... .403
MOExtended tyres................................. 375
Noise.....................................................3 95 Index
537