2018 MERCEDES-BENZ CLS air condition

Display messages
Possible causes/consequences and P Solutions
See Operator' s Man ‐
ual R
a child, a small adult or an objec t weighing less than th e system' s
weigh t threshold is locate d on th e front-passenger seat
or R
th e front-passenger seat is unoccupied
The system may detec t objects or force s applyin g additional weigh t on
th e seat .
G WARNIN G
The front-passenger fron t air bag and front-passenger knee bag may
deploy unintentionally.
There is an increased ris k of injury.X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Switc h th e ignition off .X
Ope n th e front-passenger door .X
Remove th e child and th e child restrain t system from th e front-
passenger seat .X
Mak e sur e that there are no objects on th e seat addin g to th e
weight.
The system may otherwise detec t th e additional weigh t and inter-
pre t th e seat occupant's weigh t as greate r than it actually is.X
Kee p th e seat unoccupied , close th e front-passenger door and
switch on th e ignition .X
Observ e th e PASSENGER AI R BA G OF F indicator lamp in th e center
console and th e multifunction display and chec k th e following:
Seat unoccupied and ignition switched on :R
a self-diagnosis is carrie d out . The PASSENGER AI R BA G OF F and
PASSENGER AI R BA G ON indicator lamp s mus t ligh t up simultane -
ousl y for approximately six seconds R
th e PASSENGER AI R BA G OF F indicator lamp mus t then ligh t up and
remain lit after th e self-diagnosis . If th e indicator lamp is on , th e
OCS has disabled th e front-passenger fron t air bag and front-
passenger knee bag ( Y
page 49 )R
th e Front Passenger Airbag Enable d See Operator' s Man ‐
ual or Front Passenger Airbag Disabled See Operator' s
Manual display message s mus t no t be shown in th e multifunction
display X
Wait for a period of at least 60 seconds until th e necessar y system
checks hav e been completed.X
Mak e sur e that th e display message s do no t appear in th e multi-
function display.
If these condition s are fulfilled , th e front-passenger seat can be occu-
pied again . Whether th e PASSENGER AI R BA G OF F indicator lamp
remain s lit or goe s out depend s on how OCS classifies th e occupant .
If th e condition s are no t fulfilled , th e system is no t operating correctly.X
Visit a qualified specialist workshop immediately.
Observ e th e additional information on OCS ( Y
page 49).Display messages 21 1
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Lan e Keepin g Assist
Currently Unavaila‐
ble See Operator' s
Manual or Active
Lan e Keepin g Assist
Currently Unavaila‐
ble See Operator' s
Manual Lan e Keepin g Assis t or Active Lan e Keepin g Assis t is deactivated and
temporarily inoperative.
Possibl e causes are: R
th e windshield in th e camera' s field of vision is dirtyR
visibilit y is impaire d due to heav y rain , snow or fogR
there hav e been no lan e marking s for an extended periodR
th e lan e marking s are worn, dark or covered, e.g. by dir t or snow
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Lan e Keepin g Assis t or Active Lan e Keepin g Assis t is operational
again .
If th e display message does no t disappear :X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Clean th e windshield.
Lan e Keepin g Assist
Inoperative or
Active Lan e Keepin g
Assist Inoperative Lan e Keepin g Assis t or Active Lan e Keepin g Assis t is malfunctioning .X
Visit a qualified specialist workshop .
Blind Spo t Assist
Currently Unavaila‐
ble See Operator' s
Manual or Active
Blind Spo t Assist
Currently Unavaila‐
ble See Operator' s
Manual Blind Spot Assis t or Active Blind Spot Assis t is temporarily inoperative.
Possibl e causes are: R
th e radar sensor system is outside th e operating temperature rangeR
th e radar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti c radiation emitted by nearby TV or radi o station s or
other source s of electromagneti c radiation
The yellow c indicator lamp s also ligh t up in th e exterio r mirrors.
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Blind Spot Assis t or Active Blind Spot Assis t is operational again .
If th e display message does no t disappear :X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Restart th e engine.
Blind Spo t Assist
Inoperative or
Active Blind Spo t
Assist Inoperative Blind Spot Assis t or Active Blind Spot Assis t is malfunctioning .
The yellow c indicator lamp s also ligh t up in th e exterio r mirrors.X
Visit a qualified specialist workshop .
Par k Assist Canceled The driver's door is open and th e driver's seat belt has no t been fas -
tened. X
Repeat th e parking process wit h th e seat belt fastene d and th e
driver's door closed .Display messages 21 7
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
DTR+: Steering
Assist . Currently
Unavailable See
Operator' s Manual Steering Assis t and Stop&Go Pilo t are temporarily inoperative.
Possibl e causes are: R
th e windshield in th e camera' s field of vision is dirtyR
visibilit y is impaire d due to heav y rain , snow or fogR
there hav e been no lan e marking s for an extended periodR
th e lan e marking s are worn, dark or covered, e.g. by dir t or snow
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Steering Assis t and Stop&Go Pilo t are operative again .
If th e display message does no t disappear :X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Clean th e windshield.
DTR+: Steering
Assist . Inoperative Steering Assis t and Stop&Go Pilo t are defective.
However, th e DISTRONI C PLU S function s are still available.
A warning tone also sounds. X
Visit a qualified specialist workshop .
Cruise Contro l Inop‐
erativ e Cruis e control is malfunctioning .
A warning tone also sounds. X
Visit a qualified specialist workshop .
Cruise Contro l
- - - mph A condition for activating cruise control has no t been fulfilled .
You hav e tried to store a speed belo w 20 mph (30 km/ h) , for example.X
If conditions permit, drive faster than 20 mph (30 km/ h) and store
the speed. X
Check the activation conditions for cruise control ( Y
page 148).
Cruise Control Off Cruise control has been deactivated.
If a warning tone also sounds, cruise control has deactivated auto-
matically ( Y
page 148).220
Display messages
On-board computer and displays

Tires Display messages
Possible causes/consequences and P Solutions
Check
Tire Pressure Soon The tire pressure loss warning system has detected a significant loss
in pressure.
A warning tone also sounds.
Possible causes: R
you have changed the positions of the wheels and tires or installed
new wheels and tires. R
the tire pressure in one or more tires has dropped.
G WARNING
Tire pressures that are too low pose the following hazards: R
they may burst, especially as the load and vehicle speed increase. R
they may wear excessively and/or unevenly, which may greatly
impair tire traction. R
the driving characteristics, as well as steering and braking, may be
greatly impaired.
There is a risk of an accident. X
Stop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so. X
Secure the vehicle against rolling away ( Y
page 141).X
Check the tires and, if necessary, follow the instructions for a flat
tire ( Y
page 278). X
Check the tire pressures and, if necessary, correct the tire pressure. X
Restart the tire pressure loss warning system when the tire pres-
sure is correct ( Y
page 299).
Check Tire Pressure
Then Restart Run
Flat Indicator The tire pressure loss warning system generated a display message
and has not been restarted since. X
Set the correct tire pressure in all four tires. X
Restart the tire pressure loss warning system ( Y
page 299).
Run Flat Indicator
Inoperative The tire pressure loss warning system is faulty. X
Visit a qualified specialist workshop.
Correct
Tire Pressure The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great. X
Check the tire pressures at the next opportunity ( Y
page 299).X
If necessary, correct the tire pressure. X
Restart the tire pressure monitor ( Y
page 302).Displa y messages 22 1
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Check
Tires The tire pressur e in on e or mor e tires has dropped significantly. The
whee l position is shown in th e multifunction display.
A warning tone also sounds.
G WARNIN G
Tir e pressures that are to o low pos e th e followin g hazards :R
they may burst, especially as th e load and vehicl e speed increase.R
they may wear excessivel y and/o r unevenly, whic h may greatl y
impair tire traction .R
th e drivin g characteristics , as well as steering and braking , may be
greatl y impaired.
There is a ris k of an accident.X
Stop th e vehicl e without making any sudden steering or braking
maneuvers . Pay attention to th e traffic condition s as you do so.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Chec k th e tires and , if necessary, follow th e instruction s for a flat
tire ( Y
page 278). X
Chec k th e tire pressur e ( Y
page 299).X
If necessary, correc t th e tire pressure.
Warnin g
Tir e Malfunction The tire pressur e in on e or mor e tires has dropped suddenly. The whee l
position is shown in th e multifunction display.
G WARNIN G
Drivin g wit h a flat tire poses a ris k of th e followin g hazards :R
a flat tire affects th e abilit y to steer or brak e th e vehicle.R
you could lose control of th e vehicle.R
continued drivin g wit h a flat tire will caus e excessive heat build-up
and possibl y a fire.
There is a ris k of an accident.X
Stop th e vehicl e without making any sudden steering or braking
maneuvers . Pay attention to th e traffic condition s as you do so.X
Secur e th e vehicl e against rollin g away ( Y
page 141).X
Chec k th e tires and , if necessary, follow th e instruction s for a flat
tire ( Y
page 278).
Tir e Press. Monito r
Currently Unavaila‐
ble Becaus e there is interferenc e from a stron g source of radi o waves, no
signals from th e tire pressur e sensor s are detected. The tire pressur e
monitor is temporarily malfunctioning .X
Drive on .
The tire pressur e monitor restarts automatically as soo n as th e
problem has been resolved.
TirePress . Sen ‐
sor(s) Missin g There is no signal from th e tire pressur e sensor of on e or several
wheels. The pressur e of th e affecte d tire does no t appear in th e mul-
tifunction display. X
Hav e th e fault y tire pressur e sensor replace d at a qualified special -
ist workshop .222
Display messages
On-board computer and displays

Safety systems Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
'M
Q ' (USA only) or M (Canada only): the red brake system warning lamp is
lit while the vehicle is moving. A warning tone also sounds.
You are driving with the parking brake applied. X
Release the parking brake.
The warning lamp goes out and the warning tone ceases.
'M
Q ' (USA only) or M (Canada only): the red brake system warning lamp is
lit while the engine is running. A warning tone also sounds.
G WARNING
The brake boosting effect is malfunctioning and the braking characteristics may be
affected.
There is a risk of an accident. X
Pull over and stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions. Do not continue driving under any circumstances. X
Secure the vehicle against rolling away ( Y
page 141).X
Consult a qualified specialist workshop. X
Observe the additional display messages in the multifunction display.
'M
Q ' (USA only) or M (Canada only): the red brake system warning lamp is
lit while the engine is running. A warning tone also sounds.
G WARNING
There is not enough brake fluid in the brake fluid reservoir.
The braking effect may be impaired.
There is a risk of an accident. X
Pull over and stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions. Do not continue driving under any circumstances. X
Secure the vehicle against rolling away ( Y
page 141).X
Do not add brake fluid. Adding more will not correct the malfunction. X
Consult a qualified specialist workshop. X
Observe the additional display messages in the multifunction display.228
Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
t
Q Mercedes-AMG vehicles only:
The yellow SPORT handling mode warning lamp is lit while the engine is running.
SPORT handling mode is activated.
G WARNING
When SPORT handling mode is switched on, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident. X
Only switch to SPORT handling mode in accordance with the conditions descri-
bed in the "Activating/deactivating ESP" section ( Y
page 71).
u
Q The red restraint system warning lamp is lit while the engine is running.
The restraint system is malfunctioning.
G WARNING
The air bags or Emergency Tensioning Devices may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury. X
Observe the additional display messages in the multifunction display. X
Drive on carefully. X
Have the restraint system checked immediately at a qualified specialist work-
shop.
Observe the additional information on restraint systems ( Y
page 41).Warning and indicator lamps in the instrument cluster 231
On-board computer and displays Z

Tires Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
w
Q The yellow combination low tire pressure telltale/TPMS malfunction telltale for
the TPMS (pressure loss or malfunction) is lit.
The tire pressure monitor has detected a loss of pressure in at least one of the tires.
G WARNING
Tire pressures that are too low pose the following hazards: R
they may burst, especially as the load and vehicle speed increase. R
they may wear excessively and/or unevenly, which may greatly impair tire trac-
tion. R
the driving characteristics, as well as steering and braking, may be greatly
impaired.
There is a risk of an accident. X
Stop the vehicle without making any sudden steering or braking maneuvers. Pay
attention to the traffic conditions as you do so. X
Secure the vehicle against rolling away ( Y
page 141).X
Observe the additional display messages in the multifunction display. X
Check the tires and, if necessary, follow the instructions for a flat tire
( Y
page 278). X
Check the tire pressure ( Y
page 299).X
If necessary, correct the tire pressure.
w
Q The yellow tire pressure monitor warning lamp (pressure loss/malfunction)
flashes for approximately one minute and then remains lit.
The tire pressure monitor is faulty.
G WARNING
The system is possibly unable to recognize or register low tire pressure.
There is a risk of an accident. X
Observe the additional display messages in the multifunction display. X
Visit a qualified specialist workshop immediately.Warning and indicator lamps in the instrument cluster 235
On-board computer and displays Z