coolant level MERCEDES-BENZ GL-Class 2014 X166 Owner's Manual

Central locking
Automatic locking (on-board
computer) ...................................... 284
Locking/unlocking (SmartKey) ........80
Changing bulbs
Brake lamps ................................... 140
High-beam headlamps ...................139
Low-beam headlamps ....................138
Child-proof locks
Important safety notes ....................65
Rear doors ....................................... 66
Children
In the vehicle ................................... 60
Restraint systems ............................ 60
Special seat belt retractor ...............63
Child seat
LATCH-type (ISOFIX) child seat
anchors ............................................ 63
Top Tether ....................................... 64
Cigarette lighter ................................ 352
Cleaning Mirror turn signal ........................... 380
Trailer tow hitch ............................. 381
Climate control
3-zone automatic climate control
with additional rear-compartment
climate control ............................... 152
Automatic climate control (3-zone) 150
Controlling automatically ...............156
Cooling with air dehumidification ..155
Defrosting the windows .................160
Defrosting the windshield ..............159
Dual-zone automatic climate
control ........................................... 147
Important safety notes ..................146
Indicator lamp ................................ 156
Information about using 3-zone
automatic climate control ..............154
Maximum cooling .......................... 159
Notes on using dual-zone
automatic climate control ..............149
Overview of systems ......................146
Problems with cooling with air
dehumidification ............................ 156
Problem with the rear window
defroster ........................................ 161
Rear control panel .........................150Rear control panel (3-zone
automatic climate control with
additional rear-compartment
climate control)
............................. 152
Refrigerant ..................................... 452
Refrigerant filling capacity .............452
Setting the air distribution .............158
Setting the airflow .........................158
Setting the air vents ......................162
Setting the climate mode (AIR
FLOW) ............................................ 157
Setting the temperature ................157
Switching air-recirculation mode
on/off ............................................ 161
Switching on/off ........................... 154
Switching residual heat on/off ......161
Switching the rear window
defroster on/off ............................ 160
Switching the ZONE function on/
off .................................................. 159
Coat hooks ......................................... 347
Cockpit Overview .......................................... 32
see Instrument cluster
COLLISION PREVENTION ASSIST
Operation/notes .............................. 69
COMAND
ON&OFFROAD menu .....................262
see separate operating instructions
COMAND display
Cleaning ......................................... 381
Combination switch ..........................131
Consumption statistics (on-board
computer) .......................................... 275
Convenience closing feature ..............95
Convenience opening feature ............95
Coolant (engine) Checking the level .........................373
Display message ............................ 306
Filling capacity ............................... 451
Important safety notes ..................450
Temperature (on-board computer) .287
Temperature gauge ........................ 272
Warning lamp ................................. 334
Cooling
see Climate control
Copyright ............................................. 30 Index
7

Vehicle emergency locking
................88
Vehicle identification number see VIN
Vehicle identification plate ..............444
Vehicle level AMG adaptive sport suspension
system ........................................... 221
Vehicle level (display message) .......310
Vehicle maintenance see ASSYST PLUS
Vehicle tool kit .................................. 386
Video Operating the DVD ......................... 279
VIN ...................................................... 444W
Warning and indicator lamps ABS ................................................ 327
Brakes ........................................... 326
Check Engine ................................. 333
Coolant .......................................... 334
Distance warning ........................... 336
DISTRONIC PLUS ........................... 336
ESP ®
.............................................. 329
ESP ®
OFF ....................................... 330
Overview .......................................... 34
PASSENGER AIRBAG OFF ................49
Reserve fuel ................................... 333
Seat belt ........................................ 324
SRS ................................................ 332
Tire pressure monitor ....................337
Warranty .............................................. 24
Washer fluid Display message ............................ 322
Wheel and tire combination
see Tires
Wheel bolt tightening torque ...........432
Wheel chock ...................................... 428
Wheels Changing a wheel .......................... 427
Checking ........................................ 405
Cleaning ......................................... 379
Cleaning (warning) .........................428
Emergency spare wheel .................439
Important safety notes ..................404
Interchanging/changing ................427
Mounting a new wheel ...................431Mounting a wheel
.......................... 428
Overview ........................................ 404
Removing a wheel ..........................431
Storing ........................................... 428
Tightening torque ........................... 432
Wheel size/tire size .......................432
Window curtain air bag
Display message ............................ 300
Operation ........................................ .48
Windows
see Side windows
Windshield
Defrosting ...................................... 159
Infrared reflective .......................... 367
Windshield washer fluid
see Windshield washer system
Windshield washer system
Adding washer fluid .......................374
Notes ............................................. 451
Windshield wipers
Problem (malfunction) ...................143
Rear window wiper ........................141
Replacing the wiper blades ............141
Switching on/off ........................... 140
Winter driving
Slippery road surfaces ...................196
Snow chains .................................. 407
Winter operation
General notes ................................ 406
Overview ........................................ 406
Radiator cover ............................... 371
Snow drive program ....................... 255
Winter tires
M+S tires ....................................... 406
Wiper blades
Cleaning ......................................... 379
Important safety notes ..................141
Replacing ....................................... 141
Replacing (rear window) ................142
Replacing (windshield )................... 141
Wooden trim (cleaning instructions) 382
Workshop see Qualified specialist workshop Z
ZONE function Switching on/off ........................... 15922
Index

Problems with the engine
Problem Possible causes/consequences and
M
MSolutions The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
X Try to start the engine again (Y page 169). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
X Consult a qualified specialist workshop. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak
or discharged.
X
Jump-start the vehicle (Y page 395).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X
Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop. The engine is not
running smoothly and
is misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X
Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it. The coolant
temperature gauge
shows a value above
248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 373). Observe the warning
notes as you do so and add coolant if necessary. 172
DrivingDriving and parking

R
Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R If you couple up a trailer, regularly check
that the cargo is securely fastened and
make sure that the trailer lamps and (if
applicable) the trailer brakes are
functioning correctly.
R Bear in mind that the handling will be less
stable when towing a trailer than when
driving without one. Avoid sudden steering
movements.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, avoid abrupt braking. Depress
the brake pedal moderately at first, so that
the trailer can activate its own brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears on uphill or downhill
gradients, shift to a lower gear using the
left-hand steering wheel paddle shifter.
A lower gear and lower speed reduce the
risk of engine failure.
R When driving downhill, shift to a lower gear
to utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
R If the coolant temperature increases
dramatically while the air-conditioning
system is switched on, switch off the air-
conditioning system.
Coolant heat can additionally be dissipated
by opening the windows and by setting the
blower fan and the interior temperature to
maximum.
R When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination. Due to the length of your vehicle/trailer
combination, you will have to travel an
additional distance beyond the vehicle you
are overtaking before returning to the
previous lane. Decoupling a trailer
G
WARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun brake
is engaged. G
WARNING
Vehicles with level control:
The vehicle is lowered as soon as you
disconnect the trailer cable. This could result
in your limbs or those of other people that are
between the vehicle body and tires or
underneath the vehicle being trapped. There
is a risk of injury.
Make sure that nobody is in the immediate
vicinity of the wheel housings or under the
vehicle when you disconnect the trailer cable.
! Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the
rebounding of the overrun brake.
X Make sure that the automatic transmission
is set to position P.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Close all doors and the tailgate.
X Apply the trailer's parking brake.
X Detach the trailer cable and decouple the
trailer.
X Switch off the engine. 268
Towing a trailerDriving and parking

If the coolant temperature is over
248 ‡(120 †), do not continue driving. The
engine will otherwise be damaged.
The coolant temperature gauge is in the
instrument cluster on the right-hand side
(Y page 33).
Under normal operating conditions and with
the specified coolant level, the coolant
temperature may rise to 248 ‡ (120 †). Tachometer
! Do not drive in the overrevving range, as
this could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
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
conditions when temperatures are around
freezing point.
The outside temperature display is in the
multifunction display (Y page 274).
Changes in the outside temperature are
displayed after a short delay. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated (Y page 201):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 203):
One or two segments in the set speed
range light up.
R DISTRONIC PLUS detects a vehicle in front:
The segments between the speed of the
vehicle in front and the stored speed light
up. Operating the on-board computer
Overview :
Multifunction display
; Switches on the Voice Control System;
see the separate operating instructions
= Right control panel
? Left control panel
A Back button
X To activate the on-board computer: turn
the SmartKey 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. Displays and operation
273On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions b
Auto Auto
Lamp
LampFunction
Function
Inoperative
Inoperative The light sensor is defective.
X
Visit a qualified specialist workshop. b
Switch Off Lights Switch Off Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã.Adaptive Highbeam Adaptive Highbeam
Assist Inoperative Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Highbeam Adaptive Highbeam
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Adaptive Highbeam 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.
X Clean the windshield.
If the system detects that the camera is fully operational again,
the Adaptive Highbeam Assist Now Available Adaptive Highbeam Assist Now Available message is
displayed.
Adaptive Highbeam Assist is operational again. Engine
Display messages Possible causes/consequences and
M MSolutions +
Check Coolant Check Coolant
Level See Level See
Operator's Manual Operator'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 373).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. ? 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
mountainous terrain, and stop-and-go traffic. 306
Display
messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions ?
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 ( Ypage 188).
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 †).
Otherwise, 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 †). # The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. Display
messages
307On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions ?
The red coolant
warning lamp comes on
while the engine is
running.
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.
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 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 188).
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 373).
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
mountainous terrain, and stop-and-go traffic. ?
The red coolant
warning lamp comes on
while the engine is
running. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (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.
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. Warning and indicator lamps in the instrument cluster
335On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions 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 188).
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 373).
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 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
mountainous terrain, and stop-and-go traffic. Driving systems
Problem Possible causes/consequences and
M MSolutions ·
The red distance
warning function
warning lamp comes on
while the vehicle is
moving. A warning tone
also sounds.
You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Further information on DISTRONIC PLUS (Y page 203).
Further information on PRE-SAFE ®
Brake (Y page 75).
Further information on the distance warning function
(Y page 69). 336
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Example: engine oil cap
X
Turn cap :counter-clockwise and remove
it.
X Add engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick, add 1.1 US qt (1.0 l) of
engine oil.
X Replace cap :on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.
X Check the oil level again with the oil
dipstick (Y page 371).
Further information on engine oil
(Y page 449). Additional service products
Checking coolant level G
WARNING
Certain components in the engine
compartment, such as the engine, radiator
and parts of the exhaust system, can become
very hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When opening the cap, you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
X
Park the vehicle on a level surface.
Only check the coolant level when the
vehicle is on a level surface and the engine
has cooled down.
X Turn the SmartKey to position 2in the
ignition lock (Y page 167).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 167).
X Check the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position
0(Y page 167) in the ignition lock.
X Slowly turn cap :half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap :further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar =in the filler
neck when warm, there is enough coolant
in expansion tank ;. Engine compartment
373Maintenance and care Z