2019 MERCEDES-BENZ GLE ECU

X
Slide bolt 0083into the hole in the ball coupling
recess and the ball coupling to the stop. X
Secure the bolt using spring cotter 0084.X
Check the ball coupling, bolt and spring cotter
for correct installation.
If the ball coupling cannot be correctly mounted,
remove the ball coupling. Under these circum-
stances, the ball coupling must not be used for
trailer towing.
Have the entire trailer tow hitch checked at a
qualified specialist workshop. Coupling up a trailer
! Do not connect the trailer's brake system (if
featured) to the hydraulic brake system of the towing vehicle, as the latter is equipped with
an anti-lock brake system. Doing so will result
in a loss of function of the brake systems of
both the vehicle and the trailer.
X Shift the transmission to position 005D.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Vehicles with AIRMATIC Package: select
normal level and the Comfortdrive program.
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 Parking Assist PARKTRONIC
R Active Parking Assist
R Parking Package with rear view camera
R Active Blind Spot Assist
R Active Lane Keeping Assist
i Vehicles with the AIRMATIC Package: if you
couple up a trailer, the vehicle always remains
at normal level. When coupling up a trailer,
please observe the following:
R If the normal level has not been set man-
ually, the vehicle is automatically lowered
to normal level. This is the case if a speed of
5 mph (8 km/h) is reached.
R The Sport drive program is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Observe the maximum permissible trailer
dimensions (width and length). Towing a trailer
223Driving and parking Z

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-woundunder 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 triggers the
trailer brakes. Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric-
tions. Make sure that your car/trailer combina- tion complies with the local regulations:
R in your place of residence
R in the location to which you are driving
The police and local authorities can provide reli-
able information.
Observe the following when towing a trailer:
R To gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
- cornering
- stopping
- backing up
R Before driving, check:
- trailer tow hitch
- safety switch for braked trailers
- safety chains
- electrical connections
- lights
- wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer has electronically controlled
brakes, pull away carefully. Brake manually using the brake controller and check whether
the brakes function correctly.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
R When you couple up a trailer, check at regular
intervals that the load is firmly secured. If the trailer is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
R Bear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
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, do not brake suddenly, but instead
depress the brake pedal moderately at first sothat the trailer can activate its brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears on uphill or downhill gra-
dients, 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 instal- led, the trailer brakes.
R If the coolant temperature increases dramat-
ically while the air-conditioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by open-
ing the windows and switching the ventilation blower and the interior temperature to the
highest level.
R When overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of the vehicle/trailer com-
bination, you require additional road space in
relation to the vehicle you are overtaking
before you can change back to the original
lane. 224
Towing a trailerDriving and parking

Use only bicycle racks approved by
Mercedes-Benz.
Bicycle racks cause your vehicle's driving char-
acteristics to change. The vehicle:
R is heavier
R is restricted in its acceleration and gradient-
climbing capability
R has an increased braking distance This could impair the handling characteristics.
Adapt your driving style accordingly. Maintain a
safe distance and drive carefully.
When using bicycle racks, set the tire pressure
on the rear axle of the vehicle for the maximum
load. Further information on tire pressure can be
found on the tire pressure table (Y page 354).Loading instructions
The greater the distance between the load's center of gravity and the ball head, the higher the load exerted on the trailer tow hitch.
Therefore, observe the following notes:
R Attach heavy bicycles as close as possible to the vehicle.
R Always distribute the load on the bicycle rack as symmetrically as possible to the vehicle longi-
tudinal axis.
Before loading the bicycle rack, Mercedes-Benz advises you to remove all add-on parts from the
bicycles, e.g. bicycle baskets, child seats or batteries. This will allow you to improve the aerody-
namic resistance and the bicycle rack's center of gravity.
Always secure bicycles against slipping and check that they are firmly seated at regular intervals.
Do not use tarpaulins or other covers. This could impair the driving characteristics and rear visibility. The aerodynamic resistance would also rise, and so would the load exerted on the trailer tow hitchas a result. Load distribution on the bicycle rack
0043 Distance in height between the center of gravity and the ball coupling
0044 Distance to the rear between the center of gravity and the ball coupling
0087 The center of gravity is located on the central axis of the vehicle Bicycle rack
227Driving and parking Z

Display messages
Possible causes/consequences and
0050
0050Solutions The yellow
0024warning lamp and the red 0049(USA only) or 0024
(Canada only) indicator lamp light up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
or X Release the electric parking brake automatically (Y page 157).
If the electric parking brake still cannot be released:
X Do not drive on.
X Consult a qualified specialist workshop. The red
0049(USA only) or 0024(Canada only) indicator lamp flashes
and the yellow 0024warning lamp lights up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
To apply: X Switch off the ignition and turn it back on.
X Apply the electric parking brake manually.
If the red 0049(USA only) or 0024(Canada only) indicator lamp con-
tinues to flash:
X Do not drive on.
X Secure the vehicle against rolling away (Y page 372).
X Shift the transmission to position 005D.
X Turn the front wheels towards the curb.
X Consult a qualified specialist workshop. 248
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions The yellow
0024warning lamp lights up and the red 0049(USA only)
or 0024 (Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to position 005D.
X Visit a qualified specialist workshop. 0027
(USA only)
004D (Canada only)
Check Brake Fluid
Check Brake Fluid
Level
Level There is not enough brake fluid in the brake fluid reservoir. In addition,
the 0027 (USA only) or 004D(Canada only) warning lamp lights up in
the instrument cluster and a warning tone sounds.
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 156).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. 0026
Check Check
Brake
Brake Pad
PadWear
Wear The brake pads/linings have reached their wear limit.
USA only: the red
0027brake system warning lamp is lit while the
engine is running.
X Visit a qualified specialist workshop. 0053
Inoperative Inoperative One or more main features of the mbrace system are malfunctioning.
X Visit a qualified specialist workshop. Active
Active
Brake
Brake Assist
Assist
Functions
Functions Currently
Currently
Limited See Opera‐
Limited See Opera‐
tor's Manual tor's Manual Active Brake Assist with cross-traffic function is temporarily inopera-
tive.
Possible causes are:
R the radar sensor system is temporarily inoperative, e.g. due to elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
R the system is outside the operating temperature range
R the on-board voltage is too low
When the causes stated above no longer apply, the display message
disappears.
Active Brake Assist with cross-traffic function or PRE ‑SAFE®
PLUS is
functional 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 156).
X Restart the engine. 250
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions Active
Active
Brake
BrakeAssist
Assist
Functions Limited
Functions Limited
See Operator's Man‐ See Operator's Man‐
ual ual Active Brake Assist is unavailable due to a malfunction. Adaptive
Brake Assist may also have failed.
X Visit a qualified specialist workshop immediately. PRE-SAFE Inopera‐
PRE-SAFE Inopera‐
tive tive
See
SeeOperator's
Operator's
Manual
Manual Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. Active
Active
Brake
BrakeAssist
Assist
Functions
Functions Currently
Currently
Limited See Opera‐
Limited See Opera‐
tor's Manual tor's Manual Active Brake Assist or PRE‑SAFE
®
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 elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
R Mercedes-AMG vehicles: ESP ®
is deactivated
R the system is outside the operating temperature range
R the on-board voltage is too low
When the causes stated above no longer apply, the display message
disappears.
Active Brake Assist or PRE‑SAFE ®
PLUS is operative 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 156).
X Restart the engine.
X Mercedes-AMG vehicles: switch ESP ®
on again (Y page 71). Active Active
Brake
BrakeAssist
Assist
Functions Limited
Functions Limited
See Operator's Man‐ See Operator's Man‐
ual ual Active Brake Assist with cross-traffic function or PRE
‑SAFE®
PLUS is
not available due to a malfunction.
X Visit a qualified specialist workshop immediately. Display
messages
251On-board computer and displays Z

Display messages
Possible causes/consequences and
0050
0050Solutions Radar
Radar
Sensors
Sensors Dirty
Dirty
See Operator's Man‐
See Operator's Man‐
ual ual The radar sensor system is malfunctioning.
Possible causes are:
R dirt on sensors
R heavy rain or snow
R when driving on inter-urban roads without traffic or infrastructure,
e.g. in desert-like areas
At least one driving system or driving safety system is malfunctioning
or is temporarily unavailable:
R PRE-SAFE ®
PLUS
R Active Brake Assist
R Active Lane Keeping Assist
R Active Blind Spot Assist
R Active Distance Assist DISTRONIC
If the radar sensor system in front is dirty, Active Blind Spot Assist will
not perform a course-correcting brake application.
A warning tone also sounds.
Once the cause of the problem is no longer present, the driving and
drive safety systems will be available again. The display message dis-
appears.
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 156).
X Switch off the engine.
X Clean all sensors (Y page 330).
X Restart the engine.
The display message disappears. 0075
SRS SRS
Malfunction Malfunction Ser‐
Ser‐
vice Required
vice Required The restraint system is malfunctioning.
The
0075 warning lamp also lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be triggered unintentionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop immediately.
For further information about the restraint system, see (Y page 44).0075
Front Left Malfunc‐ Front Left Malfunc‐
tion Service tion Service
Required Required
orFront
Front
Left Malfunction
Left Malfunction
Service Required Service Required The restraint system has malfunctioned at the front on the left or right.
The 0075 warning lamp also lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be triggered unintentionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop immediately. 252
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions Front
Front
Passenger
Passenger Air‐
Air‐
bag Disabled See
bag Disabled See
Operator's Manual Operator's Manual The front-passenger front air bag is deactivated during the journey,
although:
R an adult
or
R a person of the corresponding stature is on the front-passenger seat
If additional forces are applied to the seat, the system may interpret
the occupant's weight as lower than it actually is.
G WARNING
The front-passenger front air bag does not deploy during an accident.
There is an increased risk of injury.
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 156).
X Switch the ignition off.
X Have the occupant on the front-passenger seat get out of the vehi-
cle.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the center
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R a self-diagnosis is carried out. The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps must light up simulta-
neously for approximately six seconds
R the PASSENGER AIR BAG OFF indicator lamp must then light up
and remain lit after the self-diagnosis. If the indicator lamp is on, OCS (vehicle Occupant Classification System) has deactivated
the front-passenger front air bag (Y page 52)
R the Front Passenger Airbag Enabled See Operator's Front Passenger Airbag Enabled See Operator's
Manual
Manual orFront Passenger Airbag Disabled See Opera‐
Front Passenger Airbag Disabled See Opera‐
tor's
tor's Manual
Manual display messages must not be shown on the mul-
tifunction display
X Wait for a period of at least 60 seconds until the necessary system
checks have been completed.
X Make sure that the display messages do not appear in the multi-
function display.
If these conditions are fulfilled, the front-passenger seat can be occu-
pied again. Whether the PASSENGER AIR BAG OFF or ON indicator
lamp remains lit or goes out depends on how OCS classifies the occu-
pant.
If the conditions are not fulfilled, the system is not operating correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System, see (Y page 52). 254
Display
messagesOn-board computer and displays