2015 MERCEDES-BENZ CLA-Class air condition

Engine
Display messages
Possible causes/consequences and
M
MSolutions +
Check Coolant Check Coolant
Level See Opera‐ Level See Opera‐
tor's Manual tor's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 289).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ? The fan motor is faulty.
X At coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. ?
Coolant Too Hot Coolant Too Hot
Stop Vehicle Turn Stop Vehicle Turn
Engine Off Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 248 ‡ (120 †). Other-
wise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). Display messages
233On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Lane Keeping
Lane Keeping
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Lane Keeping Assist is deactivated and temporarily inoperative.
Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there have been no lane markings for an extended period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
When the causes stated above no longer apply, the display mes-
sage disappears.
Lane Keeping Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Clean the windshield. Lane Keeping Lane Keeping
Assist Inoperative Assist Inoperative Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Blind Spot Assist
Blind Spot Assist
Currently Unavail‐ Currently Unavail‐
able See Opera‐ able See Opera‐
tor's Manual tor's Manual Blind Spot Assist is temporarily inoperative. Possible causes are:
R function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the radar sensor system is outside the operating temperature
range.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
When the causes stated above no longer apply, the display mes-
sage disappears.
Blind Spot Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Restart the engine. Blind Spot Assist Blind Spot Assist
Inoperative Inoperative Blind Spot Assist is defective.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. 236
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions DISTRONIC
DISTRONIC
PLUS
PLUSCur‐
Cur‐
rently
rently Unavailable
Unavailable
See
See Operator's
Operator's Man‐
Man‐
ual
ual DISTRONIC PLUS is temporarily inoperative.
Possible causes are:
R function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
When the causes stated above no longer apply, the display mes-
sage disappears.
DISTRONIC PLUS is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Restart the engine. DISTRONIC PLUS DISTRONIC PLUS
Inoperative Inoperative DISTRONIC PLUS is defective. Adaptive Brake Assist may also
have failed.
A warning tone also sounds.
X Visit a qualified specialist workshop. DISTRONIC DISTRONIC
PLUS
PLUSsus‐
sus‐
pended
pended You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X Remove your foot from the accelerator pedal. DISTRONIC PLUS
DISTRONIC PLUS
- - - mph - - - mph An activation condition for DISTRONIC PLUS is not fulfilled.
X Check the activation conditions for DISTRONIC PLUS
(Y page 171). Cruise Control
Cruise Control
Inoperative Inoperative Cruise control is malfunctioning.
A warning tone also sounds.
X Visit a qualified specialist workshop. Cruise Control Cruise Control
- - - mph - - - mph A condition for activating cruise control has not been fulfilled.
You have tried to store a speed below 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 170).238
Display messagesOn-board computer and displays

Tires
Display messages
Possible causes/consequences and
M
MSolutions Check Tire Pres‐
Check Tire Pres‐
sure Soon sure 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 instal-
led new wheels and tires.
R the tire pressure in one or more tires is not correct.
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 160).
X Check the tires and, if necessary, follow the instructions for a
flat tire (Y page 300).
X Check the tire pressures and, if necessary, correct the tire pres-
sure.
X Restart the tire pressure loss warning system when the tire
pressure is correct (Y page 326).Check Tire Pres‐ Check Tire Pres‐
sure Then Restart sure Then Restart
Run Flat Indicator Run Flat Indicator Canada only:
The tire pressure loss warning system generated a display mes-
sage 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 326).Run Run
Flat
Flat Indicator
Indicator
inoperative
inoperative Canada only:
The tire pressure loss warning system is faulty.
X Visit a qualified specialist workshop. Display
messages
239On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Please Correct
Please Correct
Tire Pressure 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 326).
X If necessary, correct the tire pressure.
X Restart the tire pressure monitor (Y page 328).Check Tires Check Tires USA only:
The tire pressure in one or more tires has dropped significantly.
The wheel position is displayed in the multifunction display.
A warning tone also sounds.
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 160).
X Check the tires and, if necessary, follow the instructions for a
flat tire (Y page 300).
X Check the tire pressure (Y page 326).
X If necessary, correct the tire pressure. 240
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Auxiliary Battery
Auxiliary Battery
Malfunction Malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X Visit a qualified specialist workshop at the next opportunity.
X Until then, set the selector lever to position Pbefore you switch
off the engine.
X Before leaving the vehicle, apply the electric parking brake. Trans.
Trans.
Oil
OilOverhea‐
Overhea‐
ted Drive on with
ted Drive on with
Care Care AMG vehicles: the transmission oil has overheated.
Manual drive program
Mand the temporarily active manual drive
program are no longer available. The engine power output is
reduced.
X Allow the vehicle to cool down. 4matic Currently 4matic Currently
Unavailable Unavailable 4MATIC has overheated. The vehicle is only driven by the front
wheels.
X Drive on.
The airflow cools 4MATIC more quickly.
When the display message goes out, 4MATIC is available again
and the vehicle is driven by all four wheels. 4matic Inoperative 4matic Inoperative 4MATIC is malfunctioning. The vehicle is only driven by the front
wheels.
X Visit a qualified specialist workshop. N The trunk lid is open.
X Close the trunk lid. M The hood is open.
A warning tone also sounds.
G WARNING
The open hood may block your view when the vehicle is in motion.
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.
X Secure the vehicle against rolling away (Y page 160).
X Close the hood. C At least one door is open. A warning tone also sounds.
X Close all the doors. 244
Display
messagesOn-board computer and displays

Safety systems
Problem
Possible causes/consequences and
M
MSolutions $
(USA only)
J (Canada only)
The red brake system
warning lamp comes on while the engine is run-
ning. A warning tone
also sounds. G
WARNING
The brake boosting effect is malfunctioning and the braking char- acteristics 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 160).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. $
(USA only)
J (Canada only)
The red brake system
warning lamp comes on while the engine is run-
ning. A warning tone
also sounds. There is not enough brake fluid in the brake fluid reservoir.
G WARNING
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 160).
X Do not add brake fluid. Adding more will not remedy the mal-
function.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. Warning and indicator lamps in the instrument cluster
249On-board computer and displays Z

Problem
Possible causes/consequences and
M
MSolutions ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may
be blocked or the electric engine radiator fan may be malfunc-
tioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 289).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
below 248 ‡(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow to the engine radiator may be blocked or the coolant level may
be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).Warning and indicator lamps in the instrument cluster
257On-board computer and displays Z