2012 MERCEDES-BENZ E-CLASS ESTATE air condition

Display messages Possible causes/consequences and
M Solutions
Lane Keeping
Assist inopera‐
tive or
Active Lane Keeping
Assist inoperative Lane Keeping Assis
torActive Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Lane Keeping
Assist currently
unavailable See
Owner's Manual or
Active Lane Keep‐ ing Assist cur‐
rently unavailable
See Owner's Manual Blind Spot Assist or Active Blind Spot Assist is temporarily inop-
erative.
You have established the electrical connection between the trailer
and your vehicle.
X Press aon the steering wheel to confirm the display mes-
sage.
Blind Spot Assist or Active Blind Spot Assist is deactivated while
towing a trailer. Blind Spot Assist or Active Blind Spot Assist is temporarily inop-
erative .Possible causes:
R the sensors are dirty.
R the function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
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.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
Once the causes listed above no longer apply, the display message
goes out.
Blind Spot Assist or Active 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 183).
X Clean the sensors (Y page 354).
X Restart the engine. Blind Spot Assist
inoperative or
Active Blind Spot Assist inoperative Blind Spot Assist or Active Blind Spot Assist is faulty.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. Display messages
285On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
DISTRONIC PLUS cur‐
rently unavailable
See Owner's Manual DISTRONIC PLU
Sis temporarily inoperative. Possible causes:
R the function is impaired due to heavy rain or snow.
R the sensors in the radiator trim and in the bumpers are dirty.
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.
Aw arning tone also sounds.
Once the causes listed abov eno longer apply, the display message
goes out.
DISTRONIC 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 183).
X Clean the sensors in the radiator trim and in the bumpers
(Y page 354).
X Restart the engine. DISTRONIC PLUS
inoperative DISTRONIC PLUS is faulty.
BAS PLUS and PRE-SAFE
®
Brake may also have failed.
Aw arning tone also sounds.
X Visi taqualified specialist workshop. DISTRONIC PLUS
inactive 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
--- km/h An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 195). DISTRONIC PLUS and
SPEEDTRONIC DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X Visit a qualified specialist workshop. Cruise control and
SPEEDTRONIC inop‐
erative SPEEDTRONIC and cruise control are malfunctioning.
Aw arning tone also sounds.
X Visi taqualified specialist workshop. Display messages
287On-board computer and displays Z

Tyres
Display messages Possible causes/consequences and
M Solutions
Tyre pressure
Check tyres The tyre pressure loss warning system has detected a significant
loss in pressure.
Aw
arning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a ris kofthe fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 183).
X If there is a flat tyre, inspect the tyres (Y page 363).
X Check the tyre pressures and, if necessary, correct the tyre
pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correct (Y page 385).Check tyre pres‐
sures
then restart Run
Flat Indicator The tyre pressure loss warning system generated a displaym
es-
sage and has not been restarted since.
X Set the correct tyre pressure in all four tyres.
X Restart the tyre pressure loss warning system (Y page 385).Run Flat Indicator
inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Tyre pressure
displayed after
driving for a few
minutes The tyre pressure monitor is measuring the tyre pressure.
X
Drive on.
The tyre pressures appear in the multifunction display after you
have been driving for a few minutes. Tyre press. monitor
inoperative The tyre pressure monitor is faulty.
X
Visit a qualified specialist workshop. Display messages
289On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Tyre press. moni‐
tor inoperative No
wheel sensors The wheels fitted do no
thave a suitable tyre pressure sensor .The
tyre pressure monitor is deactivated.
X Fit wheels with suitable tyre pressure sensors.
The tyre pressure monitor is activated automatically after driv-
ing for a few minutes. Check
tyres The tyre pressure in one or more tyres has dropped significantly.
The wheel position is displayed in the multifunction display.
Aw
arning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a ris kofthe fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 183).
X If there is a flat tyre, inspect the tyres (Y page 363).
X Check the tyre pressure (Y page 386).
X If necessary, correct the tyre pressure. 290
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
h
Tyre pressure Cau‐
tion Tyre malfunc‐
tion The tyre pressure in one or more tyres has dropped suddenly.
Aw
arning tone also sounds.
G WARNING
If you drive with a flat tyre, there is a ris kofthe following hazards:
R A flat tyre affects the ability to steer or brake the vehicle.
R You could lose control of the vehicle.
R Continued driving with a flat tyre will cause excessive heat build-
up and possibly a fire.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 183).
X If there is a flat tyre, inspect the tyres (Y page 363).h
Tyre pressure
Check tyre(s) The tyre pressure in one or more tyres has dropped significantly.
G WARNING
With tyre pressures which are too low, there is a risk of the fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R they tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 183).
X If there is a flat tyre, inspect the tyres (Y page 363).
X Check the tyre pressure (Y page 386).
X If necessary, correct the tyre pressure. h
Please correct
tyre pressure The tyre pressure is too low in at least one of the tyres, or the tyre
pressure difference between the wheels is too great.
X
Check the tyre pressures at the next opportunity
(Y page 386).
X If necessary, correct the tyre pressure. 292
Display messagesOn-board computer and displays

Safety systems
Problem Possible causes/consequences and
M Solutions
J
The yellow brake sys-
tem warning lamp
lights up while the
engine is running. G
WARNING
The brake system is malfunctioning and the braking characteris-
tics may be affected.
There is a risk of an accident.
X If the multifunction display shows a display message, please
observe this.
X Drive on carefully.
X Visit a qualified specialist workshop. J
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 183).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
The braking efficiency 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 183).
X Do not top up the brake fluid. Topping up will not rectify the
fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 300
Indicator and warning lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
?
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 mal-
functioning.
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 Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 183).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 348).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the coolant temperature is
under 120 †. The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start 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 120 †. The airflow 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.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 183).306
Indicator and warning lamps in the instrument clusterOn-board computer and displays

Tyres
Problem Possible causes/consequences and
M Solutions
h
The yellow tyre pres-
sure monitor warning
lamp is on. The tyre pressure monitor has detected a loss of pressure in at
leas
tone of the tyres.
G WARNING
With tyre pressures which are too low, there is a ris kofthe fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 183).
X Observe the additional display messages in the multifunction
display.
X If there is a flat tyre, inspect the tyres (Y page 363).
X Check the tyre pressure (Y page 386).
X If necessary, correct the tyre pressure. 308
Indicator and warning lamps in the instrument clusterOn-board computer and displays