2017 MERCEDES-BENZ GLC check engine

Problems with the transmission Problem
Possible causes/consequences and P Solutions
The transmission has
problems shifting gear. The transmission is losing oil. X
Have the transmission checked at a qualified specialist workshop
immediately.
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear. The transmission is in emergency mode.
It is only possible to shift into second gear and reverse gear.X
Stop the vehicle. X
Shift the transmission to position ] .X
Switch off the engine. X
Wait at least ten seconds before restarting the engine. X
Shift the transmission to position [ or ^ .
If [ is selected, the transmission shifts to second gear; if ^ is
selected, the transmission shifts to reverse gear. X
Have the transmission checked at a qualified specialist workshop
immediately.
Transfer case This section is only valid for vehicles with 4-
wheel drive (4MATIC). Power is always trans-
mitted to both axles.
! Performance tests may only be carried out
on a 2-axle dynamometer. The brake system
or transfer case could otherwise be damaged.
Contact a qualified specialist workshop for a
performance test.
! Since ESP ®
engages automatically, the igni-
tion must be switched off (the SmartKey or
Start/Stop button must be in position Z or
G ) if R
the electrical parking brake is being tested
using a dynamometer R
the vehicle is being towed with only one
axle raised (not permitted for vehicles with
4MATIC)
Otherwise, the brake system can be dam-
aged.
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission. Refueling
Important safety notes
G WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before
refueling.
G WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following: R
Wash away fuel from skin immediately
using soap and water. R
If fuel comes into contact with your eyes,
immediately rinse them thoroughly with148
Refueling
Driving and parking

When the DEF supply drops to a minimum, the
Remaining Starts: 16 message is shown in
the multifunction display.
The Remaining Starts: 16 message in the
multifunction display indicates how many more
times you can start the vehicle. If DEF is not
refilled, you will subsequently be unable to
start the engine .
If the 10 starts display message is shown and a
warning tone also sounds, then the DEF system
is malfunctioning. Have the DEF system
checked at a qualified specialist workshop. X
Add at least 1.3 gal (5.0 l) of DEF. X
Switch on the ignition for at least 60 seconds. X
Start the engine.
i Have the DEF tank refilled at a qualified spe-
cialist workshop.
Use the special DEF refill bottle when adding
DEF between maintenance intervals. Contact an
authorized Mercedes-Benz Center with any
questions or, if necessary, contact Roadside
Assistance ( Y
page 29).
If the outside temperature is below 12 ‡(

When you take advantage of engine braking, a
drive wheel may not turn for some time, e.g.
on a slippery road surface. This could cause
damage to the drive train. This type of damage
is not covered by the Mercedes-Benz war-
ranty.
Heavy and light loads
G WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This
increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately. Drive
on for a short while. This allows the airflow to
cool the brakes more quickly.
Wet roads 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 the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from 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 salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance. R
In order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions. R
Carefully depress the brake pedal and the
beginning and end of a journey. R
Maintain a greater distance to the vehicle
ahead.
Servicing the brakes
! The brake fluid level may be too low, if: R
if the red brake warning lamp lights up in
the instrument cluster and R
you hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
! Vehicles with 4MATIC: function or per-
formance tests may only be carried out on a 2-
axle dynamometer. If you wish to operate the
vehicle on such a dynamometer, please con-
sult a qualified specialist workshop in
advance. You could otherwise damage the
drive train or the brake system.
! Vehicles with 4MATIC: the ESP ®
system
operates automatically. If the electric parking
brake is tested on a brake dynamometer, the
engine and ignition must be switched off: turn
the SmartKey in the ignition lock to position

R
if there is a sudden change in temperature,
e.g. when driving into a heated garage in win-
ter R
if the camera lens is dirty or obstructed
Observe the notes on cleaning
( Y
page 316) R
if the rear of your vehicle is damaged. In this
case, have the camera position and setting
checked at a qualified specialist workshop
The field of vision and other functions of the rear
view camera may be restricted due to additional
accessories on the rear of the vehicle (e.g.
license plate holder, rear bicycle rack).
The rear view camera is protected from rain-
drops and dust by means of a flap. When the rear
view camera is activated, this flap opens.
The flap closes again when: R
you have finished the maneuvering process R
you switch off the engine R
you open the cargo compartment
Observe the notes on cleaning ( Y
page 316).
For technical reasons, the flap may remain open
briefly after the rear view camera has been
deactivated.
Activating/deactivating the rear view
camera
X
To activate: make sure that the Activa‐
tion by R gear function is selected in the
multimedia system (see the Digital Operator's
Manual). X
Engage reverse gear.
The rear view camera flap opens. The multi-
media system shows the area behind the vehi-
cle with guide lines.
The image from the rear view camera is avail-
able throughout the maneuvering process. X
To switch the function mode for vehicles
with trailer tow hitch: using the controller,
select symbol C for the "Reverse parking"
function or symbol D for "Coupling up a
trailer".
The symbol of the selected function is high-
lighted. X
To deactivate: shift the transmission to posi-
tion ] .
or X
Drive forwards at a speed greater than 7 mph
(12 km/h).
Multimedia display The rear view camera may show a distorted view
of obstacles, show them incorrectly or not at all.
The rear view camera does not show objects in
the following positions: R
very close to the rear bumper R
under the rear bumper R
in the area immediately above the tailgate
handle
! Objects not at ground level may appear to
be further away than they actually are, e.g.: R
the bumper of a parked vehicle R
the drawbar of a trailer R
the ball coupling of a trailer tow hitch R
the rear section of an HGV R
a slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom-
most guideline.Driving systems 183
Driving and parking Z

Warning lamp
C
Warning lamp
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp C on the correspond-
ing side lights up red. This warning is always
emitted when a vehicle enters the blind spot
monitoring range from behind or from the side.
When you overtake a vehicle, the warning only
occurs if the difference in speed is less than
7 mph (12 km/h).
If you select the reverse gear, Blind Spot Assist
is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
Collision warning If a vehicle is detected in the monitoring range of
Blind Spot Assist and you switch on the corre-
sponding turn signal, a double warning tone
sounds. The red warning lamp flashes on the
relevant exterior mirror. If the turn signal
remains on, detected vehicles are indicated by
the flashing of the red warning lamp on the exte-
rior mirror. There are no further warning tones.
Switching on Blind Spot Assist X
Make sure that Blind Spot Assist is activated
in the on-board computer ( Y
page 221).X
Turn the SmartKey to position H in the igni-
tion lock.
The red warning lamps on the exterior mirrors
light up until the engine is started. Display in the assistance graphic
When Blind Spot Assist is activated, gray radar
waves propagating backwards appear next to
the vehicle in the assistance display in the mul-
tifunction display ( Y
page 219). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green C . Blind Spot Assist is then ready for use.
Towing a trailer When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. In this event, Blind Spot Assist is deac-
tivated. The Blind Spot Assist Not Avail‐
able When Towing a Trailer See Opera‐
tor's Manual message appears in the multi-
function display.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle by means of multifunction cam-
era C which is attached behind the top of the
windshield. Active Lane Keeping Assist detects
lane markings on the road and can warn you
before you leave your lane unintentionally.Driving systems 195
Driving and parking Z

the lines in the assistance graphic
( Y
page 219) appear in green. Active Lane
Keeping Assist is ready for use. X
To deactivate: press button D .
Indicator lamp C goes out. The Active Lane
Keeping Assist is deactivated. The Lane
Keeping Assist Off message appears on
the multifunction display.
Selecting Standard or Adaptive setting X
In the DriveAssist menu on the on-board
computer, select the Active Lane Keep‐
ing Assist function ( Y
page 221).X
Select setting Standard or Adaptive .
When Standard is selected, no warning vibra-
tion occurs if: R
you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time. R
a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
When Adaptive
is selected, no warning vibra-
tion occurs if: R
you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time. R
a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.R
you accelerate hard, e.g. kickdown. R
you brake hard. R
you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly. R
you cut the corner on a sharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system recognizes certain conditions
and warns you accordingly.
The warning vibration occurs earlier if: R
you approach the outer lane marking on a
bend. R
the road has very wide lanes, e.g. a highway. R
the system detects solid lane markings.
The warning vibration occurs later if: R
the road has narrow lanes. R
you cut the corner on a bend.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection. This can be accomplished by checking the trailer
lighting.
Towing a trailer
Important safety notes
G WARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the
ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" ( Y
page 371).
G WARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi-
cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
! If you have a trailer tow hitch retrofitted,
changes to the engine cooling system may be
necessary, depending on the vehicle type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
The installation of a trailer tow hitch is only per-
missible if a towing weight is specified in your
vehicle documents. If this is not the case, then
the vehicle is not approved for the towing of a
trailer.202
Towing a trailer
Driving an d parking

X
Switch off the engine. X
Close the doors and tailgate. X
Couple up the trailer. X
Establish the electrical connection between
the vehicle and the trailer. X
Check that the trailer lighting system is work-
ing. X
Push the combination switch upwards/down-
wards and check whether the corresponding
turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is work-
ing properly. The function of other systems also
depends on this, for example: R
ESP ®
R
PARKTRONIC R
Active Parking Assist R
Active Blind Spot Assist R
Active Lane Keeping Assist
Vehicles with AIR BODY CONTROL: if you couple
up a trailer, the vehicle always remains at high-
way level. Observe the following note when cou-
pling up a trailer: R
Unless highway level has been set manually,
the vehicle is automatically lowered to high-
way level. If a speed of 5 mph (8 km/h) has
been reached, this may be the case.
These restrictions apply to accessories that are
supplied with power via the trailer socket in your
vehicle, e.g. a rear bicycle rack.
Observe the maximum permissible trailer
dimensions (width and length).
Most U.S. states and all Canadian provinces
require by law: R
Safety chains between the towing vehicle and
the trailer. The chains should be cross-wound
under the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible. R
A separate brake system for certain types of
trailer. R
Safety switch for braked trailers. Check the
specific legal requirements applicable to your
state.
If the trailer becomes detached from the tow-
ing vehicle, the safety feature applies the
trailer brakes. Towing a trailer There are several legal requirements for towing
a trailer, e.g. the maximum permissible speed.
Make sure that your car/trailer combination
complies with the local regulations: R
in your place of residence R
at your destination
The police and local authorities can provide reli-
able information.
To accumulate driving experience and accustom
yourself to the new handling characteristics,
practice the following at a location where there
is no traffic: R
Cornering R
Stopping R
Backing up
Check the following before the journey: R
Trailer tow hitch R
Safety switch for braked trailers R
Safety chains R
Electrical connections R
Lighting system R
Wheels and tires R
Load securing
Adjust the exterior mirrors so that you have a
clear view of the rear section of the trailer.
If the trailer is equipped with electronically con-
trolled brakes, pull away carefully in the car/
trailer combination. Brake manually using the
brake controller and check whether the brakes
function correctly.
Regularly check that the load is secure.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
The vehicle/trailer combination: R
is heavier R
is restricted in its acceleration and gradient-
climbing capability R
has an increased braking distance R
is affected more by strong crosswinds R
demands more sensitive steering R
has a larger turning circle
Avoid sudden steering movements.
Avoid braking abruptly. If possible, brake gently
at first to allow the trailer to run on. Then,
increase the braking force rapidly.Towing a trailer 205
Driving and parking Z

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 ] .X
Visit a qualified specialist workshop .
' (USA
only)
M ( Canada
only)
Check Brake Fluid
Level There is no t enough brak e flui d in th e brak e fluid reservoir .
In addition , th e ' (US A only) or M (Canada only) warning lamp
lights up in th e instrumen t cluste r and a warning tone sounds.
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 154).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.
US A only: th e ' red brak e system warning lamp is lit while th e
engin e is running. 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 .
Collision Preven ‐
tio n Assist Plu s
Currently Unavaila‐
ble See Operator' s
Manual COLLISION PREVENTION ASSIST PLU S is temporarily no t operational.
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.
COLLISION PREVENTION ASSIST PLU S 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 154).X
Restart th e engine. Display messages 23 3
On-board computer and displays Z