2019 MERCEDES-BENZ GLS SUV stop start

Display messages
Possible causes/consequences and
0050
0050Solutions Active Parking Assist is unavailable or faulty.
X Switch off the ignition and restart the engine.
If Active Parking Assist continues to be unavailable (the 005Dsymbol
does not appear on the multifunction display):
X Visit a qualified specialist workshop. Active Parking
Active Parking
Assist Finished Assist Finished The vehicle is parked. A warning tone also sounds.
The display message disappears automatically. Active Distance
Active Distance
Assist Off Assist Off Active Distance Assist DISTRONIC was deactivated.
If a warning tone also sounds, the Active Distance Assist DISTRONIC
has deactivated automatically (Y page 172).Active Distance Active Distance
Assist Assist
Now
NowAvailable
Available Active Distance Assist DISTRONIC is operational again after having
been temporarily unavailable. You can now reactivate Active Distance
Assist DISTRONIC (Y page 172).Active Distance Active Distance
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Active Distance Assist DISTRONIC is temporarily inoperative.
Active Steering Assist is also temporarily inoperative.
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
A warning tone also sounds.
When the causes stated above no longer apply, the display message
disappears.
Active Distance Assist 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 158).
X Restart the engine. Active Distance Active Distance
Assist Inoperative Assist Inoperative Active Distance Assist DISTRONIC is faulty.
The following may have also failed:
R Active Brake Assist
R Active Brake Assist with cross-traffic function
A warning tone also sounds.
X Visit a qualified specialist workshop. Act. Distance Act. Distance
Assist Suspended Assist Suspended You have depressed the accelerator pedal. Active Distance Assist
DISTRONIC is no longer controlling the speed of the vehicle.
X Remove your foot from the accelerator pedal. 266
Display
messagesOn-board computer and displays

Tires
Display messages
Possible causes/consequences and
0050
0050Solutions Check
Check
Tire
TirePressure
Pressure
Soon
Soon The tire pressure loss warning system has detected a significant loss
in pressure.
A warning tone also sounds.
Possible causes:
R you have changed the positions of the wheels and tires or installed
new wheels and tires
R the tire pressure in one or more tires has dropped significantly
G WARNING
Tire pressures that are too low pose the following hazards: R they may burst, especially as the load and vehicle speed increase.
R they may wear excessively and/or unevenly, which may greatly
impair tire 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
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 158).
X Check the tires and, if necessary, follow the instructions for a flat
tire (Y page 335).
X Check the tire pressures and, if necessary, correct the tire pressure.
X Restart the tire pressure loss warning system when the tire pres-
sure is correct (Y page 359). Check Check
Tire
TirePressure
Pressure
Then Restart Run
Then Restart Run
Flat Indicator Flat Indicator The tire pressure loss warning system generated a display message
and has not been restarted since.
X Set the correct tire pressure in all four tires.
X Restart the tire pressure loss warning system (Y page 359).Run Flat Indicator Run Flat Indicator
Inoperative Inoperative The tire pressure loss warning system is faulty.
X Visit a qualified specialist workshop. 0077
Rectify Tire Pres‐ Rectify Tire Pres‐
sure sure The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
X Check the tire pressure (Y page 359).
X If necessary, correct the tire pressure.
X When the tire pressure is correct, restart the tire pressure moni-
toring system (Y page 362).268
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions 0077
Check Tire(s) Check Tire(s) The tire pressure in one or more tires has dropped significantly. The
wheel position is displayed in the multifunction display.
A warning tone also sounds.
G WARNING
Tire pressures that are too low pose the following hazards: R they may burst, especially as the load and vehicle speed increase.
R they may wear excessively and/or unevenly, which may greatly
impair tire 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
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 158).
X Check the tires and, if necessary, follow the instructions for a flat
tire (Y page 335).
X Check the tire pressure (Y page 359).
X If necessary, correct the tire pressure. 0077
Warning Tire Mal‐ Warning Tire Mal‐
function function The tire pressure in one or more tires has dropped suddenly. The wheel
position is shown in the multifunction display.
G WARNING
Driving with a flat tire poses a risk of the following hazards: R a flat tire affects the ability to steer or brake the vehicle
R you could lose control of the vehicle.
R continued driving with a flat tire 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
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 158).
X Check the tires and, if necessary, follow the instructions for a flat
tire (Y page 335). Tire Tire
Press.
Press. Monitor
Monitor
Currently Unavaila‐
Currently Unavaila‐
ble ble Because there is interference from a strong source of radio waves, no
signals from the tire pressure sensors are detected. The tire pressure monitor is temporarily malfunctioning.
X Drive on.
The tire pressure monitor restarts automatically as soon as the
problem has been resolved. 0077
TirePress. Sen‐ TirePress. Sen‐
sor(s) Missing sor(s) Missing There is no signal from the tire pressure sensor of one or several tires.
The pressure of the affected tire is not displayed in the multifunction
display.
X Have the faulty tire pressure sensor replaced at a qualified special-
ist workshop. Display
messages
269On-board computer and displays Z

Display messages
Possible causes/consequences and
0050
0050Solutions Tire Pressure Moni‐
Tire Pressure Moni‐
tor Inoperative No tor Inoperative No
Wheel Sensors Wheel Sensors The wheels mounted do not have a suitable tire pressure sensor. The
tire pressure monitor is deactivated.
X Mount wheels with suitable tire pressure sensors.
The tire pressure monitor is activated automatically after driving for a few minutes. Tire
Tire
Press.
Press. Monitor
Monitor
Inoperative
Inoperative The tire pressure monitor is faulty.
X Visit a qualified specialist workshop. Vehicle
Display messages
Possible causes/consequences and
0050
0050Solutions Shift
Shift
to
to'P'
'P' or
or'N'
'N'
to Start Engine
to Start Engine You attempted to start the engine with the transmission in position
005E
or 005B.
X Shift the transmission to position 005Dor005C. Apply Brake to
Apply Brake to
Shift from 'P' Shift from 'P' You attempted to shift the transmission to position
005B,005Eor005C
without depressing the brake pedal.
X Depress the brake pedal. To
To
Deselect
Deselect P
Por
or N,
N,
Depress Brake and
Depress Brake and
Start Engine Start Engine You attempted to shift the transmission out of position
005Dor005C into
another transmission position with the engine switched off.
X Depress the brake pedal.
X Start the engine. Apply Brake to
Apply Brake to
Select R Select R You have attempted to shift from position
005Bto position 005Ewithout
applying the brakes.
X Depress the brake pedal.
X Shift the transmission to position 005E. Driver's Door Open
Driver's Door Open
& Transmission Not & Transmission Not
in P Risk of Vehi‐ in P Risk of Vehi‐
cle Rolling Away cle Rolling Away The driver's door is open or not fully closed and the transmission is in
position 005E,005Cor005B.
A warning tone also sounds.
G WARNING
The vehicle may roll away.
There is a risk of an accident.
X Shift the transmission to position 005D.
X Secure the vehicle against rolling away (Y page 158).
X Close the driver's door completely. Only Shift to 'P' Only Shift to 'P'
when when
Vehicle
Vehicle is
isSta‐
Sta‐
tionary
tionary The vehicle is moving.
X
Stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions.
X Shift the transmission to position 005D. 270
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions 00AF
Key Not Detected Key Not Detected
(red display message) The SmartKey is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
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 158).
X Locate the SmartKey. Because there is interference from a strong source of radio waves, the
SmartKey is not detected whilst the engine is running.
A warning tone also sounds.
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 158).
X Insert the SmartKey into the ignition lock and drive in SmartKey
mode. 00AF
Remove 'Start' But‐ Remove 'Start' But‐
ton and Insert Key ton and Insert Key R
The SmartKey detection function has a temporary malfunction or is
faulty.
R The SmartKey is continually undetected.
A warning tone also sounds.
X Insert the SmartKey into the ignition lock and turn it to the desired
position.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
General notes
Some systems carry out a self-diagnosis when the ignition is switched on. Therefore, some indicator and warning lamps may light up or flash temporarily. This behavior is non-critical. These indicator
and warning lamps only indicate a malfunction if they light up or flash after starting the engine or
whilst driving. 274
Wa
rning and indi cator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00B6
0051
The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the 00B9Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler cap.
X If the fuel filler cap is closed: visit a qualified specialist workshop.00AC
0051
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the scale.
The temperature sensor for the coolant temperature gage is malfunctioning.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
X Secure the vehicle against rolling away (Y page 158).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
283On-board computer and displays Z

Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 00AC
0051
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 defective.
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 158).
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 324).
X If you have to add 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 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 heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic. 00AC
0051
The red coolant warning lamp comes on while the engine is running.
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.
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 158).
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 324).
X If you have to add 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 snow,
slush or ice. 284
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
The cooling system is pressurized, particularly when the motor is warm. If you open the cap, you could be scalded if hot coolant sprays out.
There is a risk of injury.
Let the engine cool down before you open the
cap. Wear protective gloves and protective
eyewear when opening. Open the cap slowly
to release pressure.
The coolant level may only be checked and cool- ant refilled when the engine and engine coolingsystem have cooled down. G
WARNING
Windshield washer concentrate is highly flam- mable. If windshield washer concentrate getsonto hot components of the engine or the
exhaust system, it can ignite. There is a risk of
fire and injury.
Make sure that windshield washer concen-
trate is not spilled in the vicinity of the filler
neck.
Checking coolant level 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 0048in the igni-
tion lock (Y page 140).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 142).X
Check the coolant temperature gauge in the
multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position in the ignition
lock 0092(Ypage 140).
X On vehicles with KEYLESS-GO, press the
Start/Stop button (Y page 142).
X Press the Start/Stop button (Y page 142).
X Slowly turn cap 0043half a turn counter-clock-
wise and allow excess pressure to escape.
X Turn cap 0043further counter-clockwise and
remove it.
If the coolant is at the level of marker bar 0087
in the filler neck when cold, there is enough
coolant in coolant expansion tank 0044.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar 0087in the filler neck
when warm, there is enough coolant in expan- sion tank 0044.
X If necessary, add coolant that has been tested
and approved by Mercedes-Benz.
X Replace cap 0043and turn it clockwise as far as
it will go.
For further information on coolant, see
(Y page 387).
Adding washer fluid to the windshield
washer system Example: washer fluid reservoir
X To open: pull cap0043upwards by the tab.
X Add the premixed washer fluid.
X To close: press cap 0043onto the filler neck
until it engages.
If the washer fluid level drops below the recom- mended minimum of 1 liter, a message appears in the multifunction display prompting you to
add washer fluid (Y page 273).324
Engine compartmentMaintenance and care