2021 MERCEDES-BENZ B-CLASS HATCHBACK trailer

V
V
ehicle
ehicle Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/conseq uences and
uences and0050
0050Solutions
Solutions
0072
Vehicle is operational
Switch off ignition before
exiting *Y
ou are leaving theve hicle in a ready-to-drive state. #
Get out of theve hicle, secure it against rolling away and take theke y with you. #
Ifyo u do not lea vetheve hicle, switch o. the electrical consumers, e.g. the seat heating. Otherwise, the 12‑V bat-
te ry may dischar geand starting the engine may be possible only with the help of a second battery (jump start).
ï
Check trailer hitch
lock (white display message) *T
he trailer hitch is not operational during a jou rney with a trailer. &
W WARNING
ARNING Risk of an accident if the ball neck is not loc ked
The trailer may become de tach ed. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedu reand do not re-couple the trailer until the display message disappears. #
Initiate a new swivel mo vement (/ page 274). #
When the display message disappears, couple up the trailer and drive on.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. 432
432
Display messages and
warning/indicator lamps

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe unloc ked
ball nec k. #
Consult a quali/ed specialist workshop.
*W hen theve hicle is stationary with a coupled trailer, the trailer hitch is not operational. #
Uncouple the coupled trailer and secure it against rolling away. #
If t If the ball nec he ball nec k has been f
k has been f olded in:
olded in:unlockthe ball neck (/ page 274). #
Swivel the ball neck into the end position manually and let it engage. #
If t
If the ball nec
he ball nec k has been f
k has been f olded out
olded out::unlock the ball neck (/ page 274). #
Swivel the ball neck beneath the bumper manually and let it engage.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe unloc ked
ball nec k. #
Consult a quali/ed specialist workshop.
Head-up display currently
unavailable See Owner's
Manual *T
he head-up displ ayistemp orarily una vailable. Possible causes:
R malfunctions in the po wer supply
R signal inter fere nce #
Stop in accordance with the tra1c conditions and switch theve hicle o. and on again. #
Ifth e display message still appears, consult a quali/ed specialist workshop. Displ
aymessages and warning/indicator lamps
433 433

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
or #
Stop theve hicle in accordance with the tra1c conditions and restart theve hicle. #
Ifth e display message does not disappear: consult a quali/ed specialist workshop.
Blind Spot Assist currently
unavailable See Owner's
Manual *B
lind Spot Assist is temp orarily una vailable.
The system limits ha vebeen reached (/ page 252).
Once the cause of the problem is no longer present, the system will be available again. #
Drive on
or #
Ifth e display message does not disappear, stop theve hicle in accordance with the tra1c conditions and restart
th eve hicle.
Blind Spot Assist inopera-
tive *B
lind Spot Assist is malfunctioning. #
Drive on
or #
Stop theve hicle in accordance with the tra1c conditions and restart theve hicle. #
Ifth e display message does not disappear: consult a quali/ed specialist workshop.
Blind Spot Assist not availa-
ble when towing a trailer
See Owner's Manual *W
hen you establish the electrical connection tothe trailer, Blind Spot Assist will be una vailable. #
Press the leT-hand Touch Control and ackno wledge the display message. Display messages and
warning/indicator lamps
457
457

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
Active Blind Spot Assist
currently unavailable See
Owner's Manual *A
ctive Blind Spot Assist is temp orarily una vailable.
The system limits ha vebeen reached (/ page 252).
Once the cause of the problem is no longer present, the system will be available again. #
Drive on
or #
Ifth e display message does not disappear, stop theve hicle in accordance with the tra1c conditions and restart
th eve hicle.
Active Blind Spot Assist
inoperative *A
ctive Blind Spot Assist is malfunctioning. #
Drive on
or #
Stop theve hicle in accordance with the tra1c conditions and restart theve hicle. #
Ifth e display message does not disappear: consult a quali/ed specialist workshop.
Active Blind Spot Assist
not available when towing
a trailer See Owner's Man-
ual *W
hen you establish the electrical connection tothe trailer, Active Blind Spot Assist will be una vailable. #
Press the leT-hand Touch Control and ackno wledge the display message.
Active Lane Keeping Assist
currently unavailable See
Owner's Manual *A
ctive Lane Keeping Assist is temp orarily una vailable.
The ambient conditions are outside the system limits (/ page 255).
As soon as the ambient conditions are within the system limits, the system will become available again. 458 458
Displ
aymessages and warning/indicator lamps

W
W
ar
ar ning and indicat
ning and indicat or lam
or lamps
ps Ov
Ov
er
ervie
vie w of indicat
w of indicat or and w
or and war
arning lam
ning lam ps
ps Some systems will per
form a self-test when the
ve hicle is switched on. Some indicator and warn-
ing lamps may brie0y light up or 0ash. This beha v-
iour is non-critical. These indicator and warning
lamps indicate a malfunction only if they light up
or 0as haTer theve hicle has been star ted or dur-
ing a journe y.
S
S t
tandar
andar d ins
d instr
trument displ ay
ument display W
W
idescr
idescr een coc
een coc kpit ins
kpit instrtrument display
ument display Depending on
the display setting, the positions of
th e indicator lamps on the inst rument display may
di.er from theex ample shown.
Indicat
Indicat or and w
or and w ar
arning lam
ning lam ps:
ps:
0075 Restraint system (/ page 480)
00E9 Seat belt (/ page 480)
_ Reduced po wer (/ page 482)
00D6 System error (/ page 482)
003D Electricalfault (/ page 482)
ï Trailer hitch (/ page 483)
Ù Powe r steering (/ page 483) ÿ
V
V ehicles wit
ehicles wit h a widescr
h a widescr een coc
een cockpit
kpit:
:
coolant temp erature (/ page 484)
00B9 Engine diagnostics (/ page 484)
0028 V
Vehicles wit
ehicles wit h a diesel engine:
h a diesel engine: preglow
003D Electricalfault (/ page 484)
00D4 Reser vefuel wi thfuel /ller 0ap loca-
tion indicator (/ page 484)
0024 Electric parking brake (red)
(/page 488)
0024 Electric parking brake (yellow)
(/page 488)
004D Brakes (yellow) (/ page 488)
004D Brakes (red) (/ page 488)
L Distancewarning (/ page 490)
Ó Active Brake Assist (/ page 490)
ê Active Brake Assist (/ page 490)
0025 ABS (/page 491)
00E5 ESP®
(/ page 491)
00BB ESP®
OFF (/ page 491) Display messages and
warning/indicator lamps
479 479

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
ï
Tr ailer tow hitch warning
lamp *T
hered trailer hitch warning lamp is lit.
The trailer hitch is not operational. &
W
W ARNING
ARNING Risk of an accident if the ball neck is not loc ked
The trailer may become de tach ed. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedu reand do not re-couple the trailer until the display message disappears. #
Notethe messages on the instrument displa y.Engine
Engine
W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
ÿ
Coolant warning lamp (red) *T
he red coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The coolant le vel is too low
R The air supply tothera diator is obstructed
R The radiator fan is faulty 484
484
Display message
s andwarning/indicator lamps

006F
2nd seat row, right Not loc ked...... 437
003D 12 V battery See Owner's Man-
ual......................................................... 467
ò Acoustic presence indicator
inoperative............................................ .426
: Active Light System inoperative..... 420
0099 AdBlue system fault Emer. op.:
max. XXX km/h Start not poss. in
XXX km.................................................. 476
0099 AdBlue system fault Emer gency
op. in XXX miles See Owner's Manual.... 475
0099 AdBlue system fault Engine
start not possible................................... 476
0099 AdBlue system fault See Own-
er's Manual............................................ 475
00B3 Add 1 litre engine oil when next
re fuelling ............................................... 477
é ATTENTION ASSIST inoperati ve..... 451
é ATTENTION ASSIS T:Take a
break!.................................................... 451 :
Automatic driving lights inoper-
ative...................................................... 420
00D7 Battery overheated Stop, every-
body out! Outdoors if possible ................ 428
û Before starting the engine, turn
th e steering wheel.................................. 435
004D Brake immediately ........................ 450
Á Change key batteries .................... 417
00E5 Charger cable connected .............. 426
004D Check brake 0uid le vel.................. 450
ï Check trailer hitch lock (white
display message) .................................... 432
0077 Check tyre(s) ................................ 470
003A Clean the fuel /lter....................... 440
ÿ Coolant Stop vehicle Switch
engine o............................................... 439
0025 currently una vailable See Own-
er's Manual............................................4 62
00E5 currently una vailable See Own-
er's Manual............................................4 6300B3
Engine oil le vel cannot be meas-
ured....................................................... 478
00B3 Engine oil le velRe duce oil le vel..... 477
00B3 Engine oil le velSt op vehicle
Switch engine o.................................... 477
00B3 Engine oil pressure Stop Switch
o. engine.............................................. 478
ä Fault Drive at max. 80 km/h ......... 461
0075 Front leT malfunction Consult
wo rkshop (e xample)...............................4 14
003B inoperative Battery low................. 423
003B inoperative Char geHV battery...... 424
003B inoperati veHigh-voltage battery
ch arging inco mplete ............................... 424
003B inoperative Refuel vehicle............. .424
003B inoperative See Owner's Man........ 423
0025 inoperative See Owner's Manual.. .463
00E5 inoperative See Owner's Manual.. .464
007A inoperative See Owner's Manual.. .465
0053 Inoperative................................... 466 Index
503 503

00BD
Top up coolant See Owner ’s
Manual.................................................. 439
00B2 Top up washer 0uid...................... .437
u Towing not permitted See Own-
er's Manual ............................................ 426
0080 Trans. oil overheated Drive on
with care................................................ 444
0024 Turn on the ignition torelease
th e parking brake ................................... 449
Ú .................................................... 474
0072 Vehicle is operational Switch o.
ignition before exiting............................. 432
0077 Warning tyre defect....................... 471
0077 Wheel sensor(s) missing ................ 470
Ú XX,X l Top up AdBlue Swit chon
ignition, wait 60 sec. or eng. start not
poss...................................................... 475
"Electric" drive prog ram cur rently
una vailable............................................. 428 Ac
tive Blind Spot Assist cur rently
una vailable See Owner's Manual ............ 458
Ac tive Blind Spot Assist inoperative........ 458
Ac tive Blind Spot Assist not available
when towing a trailer See Owner's
Manual.................................................. 458
Ac tive bonnet malfunction See Own-
er's Manual............................................ 435
Ac tive Brake Assist Functions cur-
re ntly limi ted See Owner's Manual .........465
Ac tive Brake Assist Functions limi ted
See Owner's Manual.............................. 466
Ac tive Distance Assist available again ..... 454
Ac tive Distance Assist cur rently
una vailable See Owner's Manual ............ 453
Ac tive Distance Assist inoperative.......... 454
Ac tive Lane Keeping Assist cur rently
una vailable See Owner's Manual ............ 458
Ac tive Lane Keeping Assist inoperative... 459 Ac
tive Steering Assist cur rently
una vailable due tomultiple emer-
ge ncy stops........................................... 456
Ac tive Steering Assist cur rently
una vailable See Owner's Manual ............ 455
Ac tive Steering Assist inoperative...........4 55
Ad aptive Highbeam Assist cur rently
una vailable See Owner's Manual ............ 421
Ad aptive Highbeam Assist inoperative ....4 22
Ad aptive Highbeam Assist Plus cur-
re ntly una vailable See Owner's Manual ... 422
Ad aptive Highbeam Assist Plus inop-
erative.................................................. .422
Anti-theT alarm system Malfunction ....... 437
Apply brake todeselect Park (P) posi-
tion....................................................... .441
Apply brake toselect D or R ...................442
Apply brake toselect R .......................... 442
Au xiliary battery malfunction (red dis-
play message) ....................................... .446 Index
505 505