ECU MERCEDES-BENZ GLS 2019 Repair Manual

Safety systems
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 004D0027
0051
0027 (USA only), 004D(Canada only): the red brake system warning lamp is lit
while the engine is running.
A warning tone also sounds.
G WARNING
The brake boosting effect is malfunctioning and the braking characteristics may be
affected.
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 158).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 004D0027
0051
0027 (USA only), 004D(Canada only): the red brake system warning lamp is lit
while the engine is running.
A warning tone also sounds.
G WARNING
There is not enough brake fluid in the brake fluid reservoir.
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 158).
X Do not add brake fluid. Adding more will not correct the malfunction.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 0027
0051
USA only: the red brake system warning lamp is lit while the engine is running.
The multifunction display also shows a display message with the 0026symbol.
The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. 276
Warning and indicator 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

Tires
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 0077
0051
The yellow tire pressure monitor warning lamp (pressure loss/malfunction) is lit.
The tire pressure monitor has detected a loss of pressure in at least one of the tires.
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 trac-
tion.
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 Observe the additional display messages in the multifunction display.
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
0051
The yellow tire pressure monitor warning lamp (pressure loss/malfunction)
flashes for approximately one minute and then remains lit.
The tire pressure monitor is faulty.
G WARNING
The system is possibly unable to recognize or register low tire pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction display.
X Visit a qualified specialist workshop immediately. 286
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Connecting a mobile phone
(COMAND)
Requirements For telephony via the Bluetooth
®
interface, you
require a Bluetooth ®
-capable mobile phone. The
mobile phone must support Hands-Free Profile
1.0 or above.
Multimedia system:
X Select Vehicle
Vehicle007BSystem Set‐ System Set‐
tings tings007B Activate Bluetooth
Activate Bluetooth .
X Activate Bluetooth ®
0073.
Mobile phone:
X Activate Bluetooth ®
and, if necessary, Blue-
tooth ®
visibility for other devices (see the
manufacturer's operating instructions).
The Bluetooth ®
device names for all of one man-
ufacturer's products might be identical. To
make it possible to clearly identify your mobile
phone, change the device name (see the man-
ufacturer's operating instructions).
If the mobile phone supports the PBAP (Phone
Book Access Profile) and MAP (Message
Access Profile) Bluetooth ®
profiles, the follow-
ing information will be transmitted after you
connect:
R Phone book
R Call lists
R Text messages and e-mail
i Further information on suitable mobile
phones can be found at: http://
www.mercedes-benz.com/connect
i In the USA, you can get in touch with the
Mercedes-Benz Customer Assistance Center
on 1-800-FOR-MERCedes (1-800-367-6372 ).
In Canada, you can get in touch with the Cus-
tomer Relations Center on 1-800-387-0100.
Searching for and authorizing (connect-
ing) a mobile phone Before using your mobile phone with the multi-
media system for the first time, you will need to
search for the phone and then authorize (con-
nect) it. Depending on the mobile phone, author- ization either takes place by means of Secure
Simple Pairing or by entering a passkey. The
multimedia system automatically makes the procedure that is relevant for your mobile phone
available. The mobile phone is always connec-
ted automatically after authorization. Further
information on using a mobile phone with the
multimedia system (see the Digital Operator's
Manual).
If the multimedia system does not detect your
mobile phone, this may be due to particular
security settings on your mobile phone (see the manufacturer's operating instructions).
Only one mobile phone can be connected to the
multimedia system at any one time.
Searching for a mobile phone
Multimedia system:
X Select Tel/ Tel/00A7007BConn. Conn.
Device
Device007BSearch for Phones Search for Phones007BStart Start
Search
Search.
The available mobile phones are displayed.
Symbols in the device list Sym-
bol Explanation
00D3
New mobile phone found, not yet
authorized.
00DC
Mobile phone is authorized, but is
not connected.
Connecting a mobile phone
Authorization using Secure Simple Pairing:
X Select mobile phone.
A code is displayed in the multimedia system
and on the mobile phone.
X If codes match: selectYes Yeson the multimedia
system.
X Confirm code on the mobile phone. Depend-
ing on the mobile phone used, confirm the
connection to the multimedia system and for
the PBAP and MAP Bluetooth ®
profiles. The
prompt to confirm may take up to two
minutes to be displayed (see the manufactur-
er's operating instructions).
X If the codes are different: selectNo Noon the
multimedia system.
The process is canceled.
Repeat authorization. Operating system
291Multimedia system Z

Authorization by entering a passkey (passcode):
X Select the Bluetooth ®
name of the mobile
phone.
The input menu for the passkey is displayed.
X Choose a one to sixteen-digit number combi-
nation as a passkey.
X Enter the passkey on the multimedia system.
X Press 0054to confirm.
X Enter and confirm the passkey on the mobile
phone. Depending on the mobile phone used,
confirm the connection to the multimedia sys-
tem and for the PBAP and MAP Bluetooth ®
profiles. The prompt to confirm may take up
to two minutes to be displayed (see the man- ufacturer's operating instructions). Connecting a mobile phone (Audio 20)
Requirements For telephony via the Bluetooth
®
interface, you
require at least one Bluetooth ®
-capable mobile
phone depending on use of one-telephone
mode ortwo-telephone mode. The mobile
phone must support Hands-Free Profile 1.0 or
above.
In two-telephone mode you can use all the
functions of the multimedia system with the
main telephone. With the additional tele-
phone , you can receive incoming calls.
Multimedia system:
X Select Vehicle
Vehicle007BSystem Set‐ System Set‐
tings tings007B Activate Bluetooth
Activate Bluetooth .
X Activate Bluetooth ®
0073.
Mobile phone:
X Activate Bluetooth ®
and, if necessary, Blue-
tooth ®
visibility for other devices (see the
manufacturer's operating instructions).
The Bluetooth ®
device names for all of one man-
ufacturer's products might be identical. To
make it possible to clearly identify your mobile
phone, change the device name (see the man-
ufacturer's operating instructions). If the mobile phone supports the PBAP (P
hone
Book Access Profile) and MAP (Message
Access Profile) Bluetooth ®
profiles, the follow-
ing information is transmitted after you connect
the main telephone:
R Phone book
R Call lists
R Text messages and e-mail
i Further information on suitable mobile
phones can be found at: http://
www.mercedes-benz.com/connect
i In the USA, you can get in touch with the
Mercedes-Benz Customer Assistance Center
on 1-800-FOR-MERCedes (1-800-367-6372).
In Canada, you can get in touch with the Cus-
tomer Relations Center on 1-800-387-010 0.
Searching for and authorizing (connect- ing) a mobile phone Before using your mobile phone with the multi-
media system for the first time, you will need to
search for the phone and then authorize (con-
nect) it. Depending on the mobile phone, author- ization either takes place by means of Secure
Simple Pairing or by entering a passkey. The
multimedia system automatically makes the
procedure that is relevant for your mobile phone
available. The mobile phone is always connec-
ted automatically after authorization. Further
information on using a mobile phone with the
multimedia system (see the Digital Operator's
Manual).
If the multimedia system does not detect your
mobile phone, this may be due to particular
security settings on your mobile phone (see the manufacturer's operating instructions).
Searching for a mobile phone
Multimedia system:
X Select Tel/ Tel/00A7007BConn. Device Conn. Device007BCon‐ Con‐
nect New Device
nect New Device.
X Select Connect via Vehicle
Connect via Vehicle.
X Select mobile phone.
Connecting a mobile phone X One-telephone mode: selectConnect as
Connect as
New Main Phone
New Main Phone.
X Two-telephone mode: selectConnect as
Connect as
Additional Phone
Additional Phone when a mobile phone is
already connected. 292
Operating systemMultimedia system

X
Authorization using Secure Simple Pair-
ing:
A code is displayed in the multimedia system
and on the mobile phone.
X Confirm code on the mobile phone. Depend-
ing on the mobile phone used, confirm the
connection to the multimedia system and for
the PBAP and MAP Bluetooth ®
profiles. The
prompt to confirm may take up to two
minutes to be displayed (see the manufactur-
er's operating instructions).
X If the codes are different: select No
No on the
multimedia system.
The process is canceled.
Repeat authorization.
or X Authorization by entering a passkey
(passcode):
enter any one- to sixteen-digit
number sequence which you have chosen
yourself into the passkey input menu.
X Press 0054to confirm.
X Enter and confirm the passkey on the mobile
phone. Depending on the mobile phone used,
confirm the connection to the multimedia sys-
tem and for the PBAP and MAP Bluetooth ®
profiles. The prompt to confirm may take up
to two minutes to be displayed (see the man- ufacturer's operating instructions).
Symbols in the device manager The symbols are shown in color depending on
their use. Symbol Explanation
Mobile phone connected to the
multimedia system
Main telephone with full range of
functions
Additional telephone for incoming
calls in two telephone mode Media mode
General notes If you wish to play external media sources, the
appropriate media mode must already be turned
on. Further information on media mode (see the Digital Operator's Manual). The following external media sources can be
used:
R Apple ®
devices (e.g. iPhone ®
)
R USB devices (e.g. USB stick, MP3 player)
(Y page 294)
R CD
R DVD (COMAND)
R SD cards
R Via devices connected by Bluetooth ®
i Information on single CD/DVD drive or DVD
changer (see the Digital Operator's Manual).
Selecting using the device list Multimedia system:
X Select Media
Media007B Devices Devices.
The available media sources will be shown.
The 003Bdot indicates the current setting.
X Select the media source.
Playable files are played.
Inserting/removing an SD card Important safety notes
G
WARNING
SD cards are small parts. They can be swal-
lowed and cause choking. This poses an
increased risk of injury or even fatal injury.
Keep the SD card out of the reach of children. If a SD card is swallowed, seek medical atten-
tion immediately.
! If the SD card is no longer in use, you should
take it out and remove it from the vehicle.
High temperatures can damage the card.
Inserting an SD card
The SD card slot is located on the control panel. X Insert the SD card into the SD card slot until
the SD card engages. The side with the con-
tacts must face down.
Removing an SD card X Press the SD card.
The SD card is ejected.
X Remove the SD card. Operating system
293Multimedia system Z

Stowage areas
Loading guidelines
G
WARNING
If objects, luggage or loads are not secured or not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, particu-
larly in the event of sudden braking or a sud-
den change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey. G
DANGER
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the tail- gate is open while the engine is running, espe-cially if the vehicle is in motion. There is a risk of poisoning.
Always switch off the engine before opening
the tailgate. Never drive with the tailgate
open. G
WARNING
The exhaust tail pipe and tail pipe trim can
become very hot. If you come into contact
with these parts of the vehicle, you could burn
yourself. There is a risk of burns.
Always be particularly careful and supervise
children closely around the exhaust pipe and
the exhaust pipe trims. Allow these compo-
nents to cool down before touching them.
The gross vehicle weight (GVW) is the vehicle
weight including fuel, vehicle tool kit, spare
wheel, installed accessories, vehicle occupants and luggage/cargo.
Do not exceed the load limit or permitted grossvehicle weight rating (GVWR) for your vehicle.
The gross load limit and the GVWR are specified
on the vehicle identification plate on the B-pillar
of the driver's door (Y page 362).
The load must also be distributed so that the
weight on each axle never exceeds the gross
axle weight rating (GAWR) for the front and rear axles. The specifications for GVWR and GAWR
are on the vehicle identification plate on the B-
pillar of the driver's door (Y
page 362).
Observe the notes on loading the vehicle
(Y page 362).
The handling characteristics of a laden vehicle
are dependent on the distribution of the load
within the vehicle. For this reason, you should
observe the following notes when transporting a
load:
R Never exceed the maximum permissible
gross vehicle mass or the gross axle weight
rating for the vehicle (including occupants).
R The cargo compartment is the preferred place
to carry objects.
R Position heavy loads as far forward as possi-
ble and as low down in the cargo compart-
ment as possible.
R The load must not protrude above the upper
edge of the seat backrests.
R Always place the load against the rear or front
seat backrests. Make sure that the seat
backrests are securely locked into place.
R Always place the load behind unoccupied
seats if possible.
R Use the cargo tie-down rings and the parcel
nets to transport loads and luggage.
R Use cargo tie-down rings and fastening mate-
rials appropriate for the weight and size of the load.
R Secure the load with sufficiently strong and
wear-resistant tie-downs. Pad sharp edges for
protection. Stowage spaces
Important safety notes G
WARNING
If you transport objects in the vehicle interior and these are not adequately secured, they
could slip or be flung around and thereby
strike vehicle occupants. In addition, cup
holders, open stowage spaces and mobile
phone brackets may not always be able to
hold the objects placed in them in the event of an accident. There is a risk of injury, particu-
larly in the event of sharp braking or sudden
changes of direction. Stowage areas
295Stowage and features
Z

R
Always stow objects in such a way that they
cannot be tossed about in these or similar
situations.
R Always make sure that objects do not pro-
trude out of the stowage spaces, luggage
nets or stowage nets.
R Ensure that closable stowage spaces are
shut before beginning your journey.
R Always stow and secure heavy, hard, poin-
ted, sharp-edged, fragile or large objects in
the cargo compartment.
Observe the loading guidelines (Y page 295).
Glove box X
To open: pull handle 0043and open glove box
flap 0044.
X To close: fold glove box flap 0044up until it
engages.
i The glove box can be cooled and ventilated
(Y page 136). 0047
Glove box unlocked
0048 Glove box locked
The glove box can be locked and unlocked using the mechanical key. Partition
0043for stowing flat objects is located in
the upper section of the glove box. It can be
removed to increase the stowage space in the
glove box.
X To remove: pull out partition 0043.
X To install: insert partition 0043and push it back
until it engages.
Stowage compartment under the arm-
rest Vehicles without touchpad
X To open: pull handle 0043up.
The armrest folds out. 296
Stowage areasSto
wage an d features

Vehicles with touchpad and COMAND
X To open: press button 0043at the front.
Armrest 0044folds out.
Depending on the vehicle equipment, there is a multimedia connection unit with two USB ports,
e.g. for iPod ®
, iPhone ®
or MP3 player in the
stowage compartment .
i There is a removable stowage tray in the
storage compartment, in which objects such
as an iPod ®
can be stored.
Eyeglasses compartment X
To open: press marking 0043.
The eyeglasses compartment opens down.
X To close: press marking 0043again and the
eyeglasses compartment moves up and
engages.
Make sure that the eyeglasses compartment is
always closed while the vehicle is in motion.
Stowage compartment in the front cen-
ter console X
To open: slide cover 0043forwards.
Stowage compartment 0044appears.
X To close: pull cover 0043back as far as it will go. Stowage compartment in the rear
passenger compartment center con-
sole
X
To open: briefly press the stowage compart-
ment marking.
The stowage compartment opens.
i Depending on the vehicle's equipment,
there may be open stowage spaces above and
below the stowage compartment. Stowage net
G
WARNING
Vehicles with the Occupant Classification
System (OCS):
If the gross weight of the objects in the stow- age net on the back of the front-passenger
seat is greater than 4.4 lb (2 kg), OCS cannot
correctly assess the occupant's weight cate-
gory. The front-passenger front air bag could
deploy without cause, or may fail to deploy in
the event of an accident. This poses an
increased risk of injury or even fatal injury.
Always observe the permissible gross weight
of 4.4 lb (2 kg). Stow and secure heavy
objects in the cargo compartment. Stowage areas
297Stowage and features Z