engine overheat MERCEDES-BENZ GLE COUPE 2015 Owners Manual

G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine when the vehicle
is stationary. Drive off immediately. Avoid
high engine speeds and driving at full throttle
until the engine has reached its operating
temperature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles:
at low engine oil
temperatures (below +20 †), the maximum
engine speed is restricted in order to protect the engine. To protect the engine and main-
tain smooth engine operation, avoid driving at
full throttle when the engine is cold. Key positions
Key g
To remove the key
1 Power supply for some consumers, such as
the windscreen wipers
2 Ignition (power supply for all consumers)
and drive position
3 To start the vehicle
i If the key does not belong to the vehicle, it
can still be turned in the ignition lock. How-
ever, the ignition will not be switched on. The
engine cannot be started.
Start/Stop button General notes
When you insert the Start/Stop button into the ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in succession corresponds to the different key
positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in the vehicle. This occurs, for example, when starting the
engine. 146
DrivingDriving and parking

Use the left-hand gearshift paddle to shift to a
lower gear on long and steep downhill gradients.
Take particular note of this when driving a laden vehicle.
i This also applies if you have activated cruise
control, SPEEDTRONIC or DISTRONIC PLUS.
This will use the braking effect of the engine, so
less braking will be required to maintain vehicle
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly.
Heavy and light loads G
WARNING
The braking system can overheat if you leave your foot on the brake pedal while driving.
This increases the braking distance and could
even cause the braking system to fail. There is
a risk of an accident.
Never use the brake pedal as a footrest. Do
not simultaneously depress both the brake
pedal and the accelerator pedal while driving.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If heavy demands are made on the brakes, do
not park the vehicle immediately. Drive on for a
short while. This allows the airflow to cool the
brakes more quickly.
If the brakes have been used only moderately,
you should occasionally test their effectiveness.
To do this, brake more firmly from a higher
speed. This improves the grip of the brakes.
Wet road surfaces If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after a car wash or
after driving through deep water.
You will have to depress the brake pedal more
firmly. Maintain a greater distance to the vehicle in front.
After driving on a wet road or having the vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion. Limited braking performance on salt-
treated roads If you drive on salt-treated roads, a layer of salt
may form on the brake discs and pads. This can increase the braking distance considerably.
R Apply the brakes occasionally in order to pre-
vent any salt build-up. Ensure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal at the end
of the journey and when starting the next
journey.
R Maintain a much greater distance to the vehi-
cle in front.
New brake pads/linings Brake pads/linings and discs that are either new
or have been replaced only achieve optimum
braking effect after several hundred kilometres
of driving. Compensate for the reduced braking
effect by applying greater force to the brake
pedal.
For safety reasons, Mercedes-Benz recom-
mends that you only have brake pads/linings
fitted to your vehicle which have been approved
for Mercedes-Benz vehicles or which corre-
spond to an equivalent quality standard. Brake
pads/linings which have not been approved for Mercedes-Benz vehicles or which are not of an
equivalent quality could affect your vehicle's
operating safety. Driving on wet roads
Aquaplaning If water has accumulated to a certain depth on
the road surface, there is a danger of aquaplan-
ing occurring, even if:
R you are driving at low speeds
R the tyres have adequate tread depth
For this reason, drive in the following manner in the event of heavy rain or in conditions in which
aquaplaning can occur:
R lower your speed
R avoid tyre ruts
R avoid sudden steering movements
R brake carefully Driving tips
173Driving and parking Z

R
Avoid high engine speeds, except when driv-
ing on sandy and muddy routes with high driv-
ing resistance.
R Use the left-hand steering wheel gearshift
paddle to shift to a lower gear appropriate to the gradient.
R Use the left-hand gearshift paddle to shift to a
lower gear on long and steep downhill gradi-
ents.
Hill start assist will aid you when pulling away on
a hill. Further information on hill start assist
(Y page 149).
Do not shift into transmission position Nwhen
driving off-road. You could lose control of the
vehicle if you attempt to brake the vehicle using
the service brake. If the gradient is too steep for
your vehicle, back up in reverse gear.
Always observe the approach/departure angle
values (Y page 383).
Maximum gradient-climbing capability Always observe the maximum gradient climbing
ability values (Y page 384).
Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator immediately
before reaching the brow of the hill. Make use of the vehicle's own impetus to travel over the
brow.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R the vehicle from travelling too quickly down
the other side
Driving downhill R
Drive slowly.
R Do not drive at an angle down steep inclines.
Steer into the line of fall and drive with the
front wheels aligned straight. Otherwise, the
vehicle could slip sideways, tip and overturn.
R Before tackling steep downhill gradients, use
the left-hand steering wheel gearshift paddle
to shift to a lower gear.
R Activate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the vehicle is facing in the direction of the line of
fall.
R Check that the brakes are working normally
after a long downhill stretch.
i Off-road ABS is activated when the off-road
program is selected.
At speeds below 30 km/h the front wheels
lock cyclically during braking. The digging-in
effect achieved in the process reduces the
stopping distance when driving off-road. The
steerability of the vehicle is considerably
reduced if the wheels lock. Driving systems
Intelligent Drive
Mercedes-Benz Intelligent Drive stands for inno- vative driver assistance and safety systems
which enhance comfort and support the driver in
critical situations. With these intelligent co-ordi- nated systems Mercedes-Benz has set a mile-
stone on the path towards autonomous driving.
Mercedes-Benz Intelligent Drive embraces all
elements of active and passive safety in one well thought-out system – for the safety of the vehi-
cle occupants and that of other road users.
Further information on driving safety systems
(Y page 64). Cruise control
General notes Cruise control maintains a constant road speed
for you. It brakes automatically in order to avoid
exceeding the set speed. You must select a
lower gear in good time on long and steep down-
hill gradients, especially if the vehicle is laden or towing a trailer. By doing so, you will make use of
the braking effect of the engine. This relieves the load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
Use cruise control only if road and traffic con-
ditions are appropriate for maintaining a steady
speed for a prolonged period. You can store any road speed above 30 km/h. 178
Driving systemsDriving an
d parking

towing a trailer. By doing so, you will make use of
the braking effect of the engine. This relieves the load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
You can set a variable or permanent limit speed:
R variable for speed limits, e.g. in built-up areas
R permanent for long-term speed restrictions,
e.g. when driving with winter tyres fitted
(Y page 182)
i The speed indicated in the speedometer
may differ slightly from the limit speed stored.
Important safety notes If you fail to adapt your driving style, SPEED-
TRONIC can neither reduce the risk of an acci-
dent nor override the laws of physics. SPEED-
TRONIC cannot take into account road, weather or traffic conditions. SPEEDTRONIC is only an
aid. You are responsible for the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane.
If there is a change of drivers, advise the new
driver of the speed stored.
Variable SPEEDTRONIC Cruise control lever
:
To activate or increase speed
; LIM indicator lamp
= To activate at the current speed/last stored
speed
? To activate or reduce speed
A To switch between cruise control or
DISTRONIC PLUS and variable SPEED-
TRONIC
B To deactivate variable SPEEDTRONIC With the cruise control lever, you can operate
cruise control or DISTRONIC PLUS and variable
SPEEDTRONIC.
LIM indicator lamp ;on the cruise control lever
indicates which function you have selected:
R LIM indicator lamp ;
; off: cruise control or
DISTRONIC PLUS is selected.
R LIM indicator lamp ; ;on: variable SPEED-
TRONIC is selected.
You can use the cruise control lever to limit the
speed to any speed above 30 km/h while the
engine is running.
Selecting SPEEDTRONIC
If there is a change of drivers, advise the new
driver of the limit speed stored. X Check whether LIM indicator lamp ;is on.
If it is on, variable SPEEDTRONIC is already
selected.
If it is not, press the cruise control lever in the direction of arrow A.
LIM indicator lamp ;in the cruise control
lever is on. Variable SPEEDTRONIC is selec-
ted.
Storing the current speed
You can use the cruise control lever to limit the speed to any speed above 30 km/h while the
engine is running.
X Briefly press the cruise control lever up :or
down ?tippen.
The current speed is stored and shown in the
multifunction display.
Speedometer with segments: the seg-
ments light up from the start of the scale up to
the stored speed limit.
The segments in the multifunction display
light up from the start of the scale up to the
stored speed.
Storing the current speed or calling up the
last stored speed G
WARNING
If you call up the stored speed and it is lower
than the current speed, the vehicle deceler-
ates. If you do not know the stored speed, the vehicle could decelerate unexpectedly. There
is a risk of an accident.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If you Driving systems
181Driving and parking
Z

do not know the stored speed, store the
desired speed again.
X Briefly pull the cruise control lever towards
you =.
Setting a speed X To adjust the set speed in 10 km/h incre-
ments: briefly press the cruise control lever
up : beyond the pressure point for a higher
speed, or down ?for a lower speed.
or X Keep the cruise control lever pressed beyond
the pressure point until the desired speed is
set. Press the cruise control lever up :for a
higher speed or down ?for a lower speed.
X To adjust the set speed in 1 km/h incre-
ments: briefly press the cruise control lever
up : to the pressure point for a higher speed
or down ?for a lower speed.
or
X Keep the cruise control lever pressed to the
pressure point until the desired speed is set.
Press the cruise control lever up :for a
higher speed or down ?for a lower speed.
Switching SPEEDTRONIC to passive If you depress the accelerator pedal beyond the
pressure point (kickdown), SPEEDTRONIC is
switched to passive mode. The following mes-
sage appears in the multifunction display:
SPEEDTRONIC passive
SPEEDTRONIC passive.
You can then exceed the stored speed. SPEED-
TRONIC is activated again if you:
R drive slower than the stored speed without
kickdown
R set a new speed or
R call up the last speed stored again
The SPEEDTRONIC passive SPEEDTRONIC passive message in the
multifunction display disappears. Deactivating variable SPEEDTRONIC
There are several ways to deactivate variable
SPEEDTRONIC:
X Briefly press the cruise control lever forwards
B .
or X Briefly press the cruise control lever in the
direction of arrow A.
LIM indicator lamp ;in the cruise control
lever goes out. Variable SPEEDTRONIC is
deactivated.
Cruise control or DISTRONIC PLUS is selec-
ted.
It is not possible to deactivate variable SPEED-
TRONIC by braking.
i The last speed stored is cleared when you
switch off the engine.
Permanent SPEEDTRONIC
You can use the on-board computer to perma-
nently limit the speed to a value between
160 km/h(e.g. for driving on winter tyres) and
the maximum design speed (Y page 247).
Shortly before the stored speed is reached, it
appears in the multifunction display.
Permanent SPEEDTRONIC remains active even
if variable SPEEDTRONIC is deactivated.
You cannot exceed the stored limit speed, even
if you depress the accelerator pedal beyond the
pressure point (kickdown). DISTRONIC PLUS
General notes DISTRONIC PLUS regulates the speed and auto-
matically helps you maintain the distance to the
vehicle detected in front. Vehicles are detected with the aid of the radar sensor system.
DISTRONIC PLUS brakes automatically so that
the set speed is not exceeded.
You must select a lower gear in good time on
long and steep downhill gradients, especially if
the vehicle is laden or towing a trailer. By doing
so, you will make use of the braking effect of the engine. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly.
If DISTRONIC PLUS detects that there is a risk of
a collision, you will be warned visually and
acoustically. Without your intervention, 182
Driving systemsDriving and parking

Select the
Comfortdrive program using the
DYNAMIC SELECT controller (Y page 153).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permitted speed is. Observe the legally prescri-
bed maximum speed in the relevant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See the "Technical data"
section to find out whether this applies to your
vehicle (Y page 385). If you utilise any of the
added maximum rear axle load when towing a
trailer, the vehicle/trailer combination may not
exceed a maximum speed of 100 km/h for rea-
sons concerning the operating permit. This also
applies in countries in which the permissible
maximum speed for vehicle/trailer combina-
tions is above 100 km/h.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison to when driving without a trailer and it will con-
sume more fuel.
Use the left-hand gearshift paddle to shift to a
lower gear on long and steep downhill gradients.
This also applies if you have activated cruise
control, SPEEDTRONIC or DISTRONIC PLUS.
This will use the braking effect of the engine, so
less braking will be required to maintain vehicle
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips If the trailer swings from side to side:
X Do not accelerate.
X Do not countersteer.
X Brake if necessary.
R Maintain a greater distance to the vehicle in
front than when driving without a trailer.
R Avoid braking abruptly. If possible, brake gen-
tly at first to allow the trailer to run on. Then,
increase the braking force rapidly.
R The values given for gradient-climbing capa-
bilities from a standstill refer to sea level.
When driving in mountainous areas, note that
the power output of the engine, and conse- quently the vehicle's gradient-climbing capa-
bility, decrease with increasing altitude. Swinging out the ball coupling
G
WARNING
If the ball coupling is not engaged, the trailer
may come loose. There is a risk of an accident.
Make sure that the ball coupling is securely
engaged and locked in position.
! Do not attempt to speed the up the swing-
out procedure by applying additional pressure
with your foot. The system could otherwise be
mechanically damaged.
In order to tow a trailer with your vehicle, you
must swing out the ball coupling using the
switch in the driver's door or in the tailgate.
The trailer power socket is integrated into the
ball coupling and swivels out with it.
Only release the ball coupling when its range of movement is unobstructed. Folding out using the switch in the driver's
door:
X
Make sure that the vehicle is stationary.
X Shift the transmission to position P.
X Switch the ignition on.
X Pull switch :briefly.
After a short time the ball coupling swings out from under the rear bumper. It can take up to
seven seconds before the ball coupling visibly swings out.
X Remove the protective covering from the ball
coupling and store it in a safe place. 228
Towing a trailerDriving and parking

The fuel supply is interrupted to protect the
engine when the red band is reached. Outside temperature display
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Bear in mind that the outside temperature dis-
play indicates the measured air temperature
and not the road surface temperature.
The outside temperature display is in the multi-
function display (Y page 237).
A change in the outside temperature is shown in the multifunction display after a delay. Coolant temperature gauge
G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade.
The coolant temperature gauge is in the instru-
ment cluster on the right-hand side (Y page 29).
Under normal operating conditions and with the specified coolant level, the coolant temperature
may rise to 120 †.
At high outside temperatures and when driving
uphill, the coolant temperature may rise to the
end of the scale. Operating the on-board computer
Overview :
Multifunction display
; Right control panel
= Left control panel
X To activate the on-board computer: turn
the key to position 1in the ignition lock.
You can control the multifunction display and
the settings in the on-board computer using the buttons on the multifunction steering wheel.
In vehicles with the multimedia system
COMAND Online, you can find further informa-
tion on LINGUATRONIC in the separate operat-
ing instructions.
Left control panel =
; R
Calls up the menu and menu bar 9
: Press briefly:
R Scrolls through lists
R Selects a submenu or function
R In the Audio Audio menu: selects the
previous or next station, when the preset list or station list is active,
or an audio track or video scene
R In the Tel Tel(telephone) menu:
switches to the phone book and
selects a name or telephone num-
ber 236
Displays and operationOn-board computer and displays

Engine
Display messages
Possible causes/consequences and
M
MSolutions +
Top up coolant See Top up coolant See
Owner's Manual Owner'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 Top up the coolant, observing the warning notes before doing so
(Y page 321).
If you have to top up the coolant frequently: X Contact a qualified specialist workshop and have the engine cooling
system checked. ? The fan motor is faulty.
X If the coolant temperature is below 120 †, you can continue driving
to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-start traffic. ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
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.
In addition, steam from an overheated engine can cause serious
burns, which can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
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 frozen slush.
X Do not start the engine again until the display message goes out and
the coolant temperature is below 120 †. The engine may otherwisebe damaged.
X Pay attention to the coolant temperature display.
If the temperature increases again:
X Consult a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. Display messages
269On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions #
See Owner's Manual See Owner's Manual The battery is not being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
X Consult a qualified specialist workshop. #
Stop vehicle See Stop vehicle See
Owner's Manual Owner's Manual The battery is no longer being charged and the battery charge level is
too low.
A warning tone also sounds.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
X Observe the instructions in the #See SeeOwner's
Owner's Manual
Manualdisplay
message.
X Consult a qualified specialist workshop. 4
Check Check
eng.
eng.oil
oillev.
lev.
when
when next
nextrefuelling
refuelling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
! Avoid long journeys when there is too little coolant in the cooling
system. Otherwise the engine will be damaged.
X Check the oil level when next refuelling, at the latest (Y page 320).
X If necessary, top up the engine oil (Y page 320).
If you have to top up the engine oil frequently:
X Contact a qualified specialist workshop and have the engine
checked.
Information on approved engine oils can be obtained from any quali-
fied specialist workshop or on the Internet at http://bevo.mercedes-
benz.co m. 270
Display messagesOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ?
N
The red coolant warning lamp comes on while the engine is running.
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 malfunctioning.
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 traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
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 321).
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 below 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. ?
N
The red coolant warning lamp comes on while the engine is running.
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.
In addition, steam from an overheated engine can cause serious burns, which can
occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
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 321).
X If you have to top up the coolant frequently, have the engine cooling system
checked. 296
Warning and indicator lamps in the instrument clusterOn-board computer and displays