ECU MERCEDES-BENZ CLA 2017 Owner's Guide

Display messages
Possible causes/consequences and P Solutions
The yellow $ warning lamp lights up and th e red I (US A only)
or $ (Canada only) indicator lamp flashes .
It is no t possibl e to apply th e electric parking brak e manually.X
Shift th e transmission to position P .X
Visit a qualified specialist workshop .
' (USA
only)
M ( Canada
only)
Check Brake Fluid
Level There is no t enough brak e fluid in th e brak e fluid reservoir .
A warning tone sounds. The ' (US A only) or M (Canada only)
warning lamp s in th e instrumen t cluste r may also ligh t up.
G WARNIN G
The braking effec t may be impaired.
There is a ris k of an accident.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. Do no t continu e drivin g
under any circumstances. X
Secur e th e vehicl e against rollin g away ( Y
page 140).X
Consult a qualified specialist workshop .X
Do no t add brak e fluid . This does no t correc t th e malfunction .
& Check Brake Pad Wea r The brak e pads/linings hav e reached their wear limit.X
Visit a qualified specialist workshop .
S Inoperative On e or mor e main features of th e mbrace system are malfunctioning .X
Visit a qualified specialist workshop .
Active Brake Assist
Functions Currently
Limite d See Opera‐
tor's Manual Active Brake Assis t is temporarily inoperative.
Possibl e causes are: R
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 radiationR
th e system is outside th e operating temperature rangeR
th e on-boar d voltag e is to o low
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Active Brake 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 140).X
Restart th e engine.
Active Brake
Assist : System Inop‐
erativ e Active Brake Assis t is unavailable due to a malfunction . Situation -
dependen t parking assistanc e may also hav e failed.X
Visit a qualified specialist workshop immediately.194
Display messages
On-board computer and displays

Display messages
Possible causes/consequences and P Solutions
Radar Sensor s Dirty
See Operator' s Man ‐
ual The radar sensor system is malfunctioning .
Possibl e causes are: R
Dirt on sensor sR
Heavy rain or snow R
Whe n drivin g on inter-urban roads without traffic or infrastructure,
e.g. in desert-like area s
At least on e drivin g system or drivin g safet y system is malfunctioning
or is temporarily unavailable :R
Active Brake Assis tR
Distanc e Pilo t DISTRONI C
A warning tone also sounds.
Once th e caus e of th e problem is no longer present, th e drivin g and
drive safet y systems will be available again . The display message dis-
appears.
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 140).X
Switc h off th e engine.X
Clean all sensor s ( Y
page 262).X
Restart th e engine.
The display message disappears.
u SRS Malfunction Ser ‐
vic e Required The restrain t system is malfunctioning . The u warning lamp also
lights up in th e instrumen t cluster.
G WARNIN G
The air bags or Emergency Tensioning Devices may either be triggered
unintentionally or, in th e event of an accident, may no t be triggered .
There is an increased ris k of injury.X
Visit a qualified specialist workshop immediately.
Fo r further information about th e restrain t system, see ( Y
page 39) .
u Front Lef t Malfunc‐
tio n Servic e
Required or Front
Right Malfunction
Servic e Required The restrain t system is malfunctioning at th e fron t on th e lef t or right .
The u warning lamp also lights up in th e instrumen t cluster.
G WARNIN G
The air bags or Emergency Tensioning Devices may either be triggered
unintentionally or, in th e event of an accident, may no t be triggered .
There is an increased ris k of injury.X
Visit a qualified specialist workshop immediately. Display messages 19 5
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Front Passenger Air ‐
bag Disabled See
Operator' s Manual The front-passenger air bag and front-passenger knee bag are deac -
tivated during th e journey, although:R
an adult
or R
a person of th e correspondin g statur e is on th e front-passenger seat
If additional force s are applie d to th e seat , th e system may interpret
th e occupant's weigh t as lower than it actually is.
G WARNIN G
The front-passenger fron t air bag and fron t passenger knee bag may
no t be triggered in th e event of an accident.
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 140).X
Switc h th e ignition off .X
Hav e th e occupant get out of th e vehicle.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 indicator lamp s 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 simulta-
neousl y for approximately six seconds R
th e PASSENGER AI R BA G O F F indicator lamp mus t then ligh t up
and remain lit after th e self-diagnosis . If th e indicator lamp is on ,
OCS (Occupant Classification System) has disabled th e front-
passenger fron t air bag and front-passenger knee bag
( Y
page 47) R
The Front Passenger Airbag Enable d See Operator' s
Manual or Front Passenger¶Airba g Disabled¶See Opera‐
tor's Manual display message s mus t no t be shown in th e mul-
tifunction 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 or ON indicator
lamp remain s lit or goe s out depend s on how OCS classifies th e occu-
pant.
If th e condition s are no t fulfilled , th e system is no t operating correctly.X
Visit a qualified specialist workshop immediately.
Fo r further information about th e Occupant Classification System, see
( Y
page 47). Display messages 19 7
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Front Passenger Air ‐
bag Enable d See
Operator' s Manual The front-passenger air bag and front-passenger knee bag are enabled
during th e journey, eve n though :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
be triggered 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 140).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 indicator lamp s in th e center
consol e 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 simulta-
neousl 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 ,
OCS has deactivated th e front-passenger fron t air bag and front-
passenger knee bag ( Y
page 47 )R
The Front Passenger Airbag Enable d See Operator' s
Manual or Front Passenger Airbag Disabled See Opera‐
tor's Manual display message s mus t no t be shown in th e mul-
tifunction 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 or ON indicator
lamp remain s lit or goe s out depend s on how OCS classifies th e occu-
pant.198
Display messages
On-board computer and displays

Display messages
Possible causes/consequences and P Solutions
= Sto p Vehicl e See
Operator' s Manual The battery is no longer bein g charged and th e battery charg e level is
to o low.
A warning tone also sounds. X
Pull ove r and stop th e vehicl e safely and switch off th e engine, pay-
ing attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 140).X
Observ e th e instruction s in th e display message = See Oper‐
ator's Manual .X
Consult a qualified specialist workshop .

Display messages
Possible causes/consequences and P Solutions
Blind Spo t Assist
Currently Unavaila‐
ble See Operator' s
Manual Blind Spot Assis t is temporarily inoperative.
Possibl e causes are: R
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 radiationR
th e radar sensor system is outside th e operating temperature range
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 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 140).X
Restart th e engine.
Blind Spo t Assist
Inoperative Blind Spot Assis t is faulty.
The yellow c indicator lamp s also ligh t up in th e exterio r mirrors.X
Visit a qualified specialist workshop .
Parkin g Pilot Can ‐
celed 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 .
You hav e inadvertentl y touched th e multifunction steering whee l while
steering intervention was active .X
Whil e steering intervention is active , mak e sur e that th e multifunc-
tion steering whee l is no t touched unintentionally.
The vehicl e has started to skid and ES P ®
has intervened.X
Use Parking Pilo t again later ( Y
page 162).
Parkin g Pilot Inop‐
erativ e You hav e jus t carrie d out a larg e number of turnin g or parking maneu-
vers.
Parking Pilo t will become available again after approximately te n
minute s ( Y
page 162). 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
Switc h off and restar t th e engine.
If th e multifunction display still shows th e display message :X
Visit a qualified specialist workshop .
Parking Assis t PARKTRONI C is malfunctioning .X
Visit a qualified specialist workshop .206
Display messages
On-board computer and displays

Display messages
Possible causes/consequences and P Solutions
Parkin g Pilot Fin ‐
ished The vehicl e is parked. A warning tone also sounds.
The display message disappear s automatically.
Distance Pilot Off Distanc e Pilo t DISTRONI C is deactivated ( Y
page 150).
If it was no t deactivated by th e driver , a warning tone also sounds.
Distance Pilot Now
Available Distanc e Pilo t DISTRONI C is operational again after having been tem-
porarily unavailable . You can no w reactivat e Distanc e Pilo t
DISTRONI C ( Y
page 150).
Distance Pilot Cur ‐
rently Unavailable
See Operator' s Man ‐
ual Distanc e Pilo t DISTRONI C is temporarily inoperative.
Possibl e causes are: R
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 radiationR
th e system is outside th e operating temperature rangeR
th e on-boar d voltag e is to o low
A warning tone also sounds.
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Distanc e Pilo t DISTRONI C 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 140).X
Restart th e engine.
Distance Pilot Inop‐
erativ e Distanc e Pilo t DISTRONI C is malfunctioning . Situation-dependen t
parking assistanc e may also hav e failed.
A warning tone also sounds. X
Visit a qualified specialist workshop .
Distance Pilot Sus ‐
pended You hav e depressed th e accelerato r pedal . Distanc e Pilo t DISTRONI C
is no longer controllin g th e speed of th e vehicle.X
Remove your foo t from th e accelerato r pedal .
Distance Pilot
- - - mph A condition for activating Distanc e Pilo t DISTRONI C has no t been met .X
Chec k th e activation condition s for Distanc e Pilo t DISTRONI C
( Y
page 150). Display messages 20 7
On-board computer and displays Z

Tires Display messages
Possible causes/consequences and P Solutions
Check Tire Pressure
Soon Canada only:
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 140).X
Check the tires and, if necessary, follow the instructions for a flat
tire ( Y
page 266). 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 289).
Check Tire Pressure
Then Restart Run
Flat Indicator Canada only:
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 289).
Run Flat Indicator
Inoperative Canada only:
The tire pressure loss warning system is faulty. X
Visit a qualified specialist workshop.
Please Correct Tire
Pressure USA only:
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 289).X
If necessary, correct the tire pressure. X
Restart the tire pressure monitor ( Y
page 291).Displa y messages 20 9
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Check Tires US A only:
The tire pressur e in on e or mor e tires has dropped significantly. The
whee l position appear s 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 increas eR
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 impaire d
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 140).X
Chec k th e tires and , if necessary, follow th e instruction s for a flat
tire ( Y
page 266). X
Chec k th e tire pressur e ( Y
page 289).X
If necessary, correc t th e tire pressure.
Warnin g Tir e Mal ‐
function US A only:
The tire pressur e in on e or mor e tires has dropped suddenly. The whee l
position appear s 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 vehicl eR
you could lose control of th e vehicl eR
continued drivin g wit h a flat tire will caus e excessive heat build-up
and possibl y a fir e
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 140).X
Chec k th e tires and , if necessary, follow th e instruction s for a flat
tire ( Y
page 266).
Tir e Press. Monito r
Currently Unavaila‐
ble US A only:
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.210
Display messages
On-board computer and displays

Display messages
Possible causes/consequences and P Solutions
Transmission Not in
P Ris k of Vehicl e
Rollin g Awa y The driver's door is open or no t full y closed and th e transmission is in
position R , N or D .
A warning tone also sounds.
G WARNIN G
The vehicl e may rol l away.
There is a ris k of an accident.X
Shift th e transmission to position P .X
Secur e th e vehicl e against rollin g away ( Y
page 140).X
Clos e th e driver's door completely.
Servic e Required Do
Not Shift Gears
Visit Dealer You canno t chang e th e transmission position due to a malfunction .
A warning tone also sounds.
If transmission position D is selected:X
Drive to a qualified specialist workshop without shifting th e trans -
mission from position D .
If transmission position R , N or P is selected:X
Secur e th e vehicl e against rollin g away ( Y
page 140).X
Notify a qualified specialist workshop or breakdown service.
Onl y Shift to 'P'
whe n Vehicl e is Sta ‐
tionar y The vehicl e is moving .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
Shift th e transmission to position P .
To Engage Trans‐
miss. Position R
First Depres s the
Brake You hav e attempte d to shift from position D or N to transmission
position R . X
Shift th e transmission to position R while depressing th e brak e
pedal .
Reversing Not Possi‐
ble Servic e Required The automatic transmission is malfunctioning . You canno t bac k up.X
Visit a qualified specialist workshop .
Transmission Mal ‐
function The automatic transmission is malfunctioning .X
Visit a qualified specialist workshop .
Transmission Mal ‐
function Sto p The automatic transmission is malfunctioning .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 140).X
Consult a qualified specialist workshop .212
Display messages
On-board computer and displays