2017 MERCEDES-BENZ GLS check engine

Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.
Driving safety systems
Overview of driving safety systems In this section, you will find information about
the following driving safety systems: R
ABS ( A nti-lock B raking S ystem)
( Y
page 63) R
BAS ( B rake A ssist S ystem) ( Y
page 64)R
Active Brake Assist ( Y
page 64)R
ESP ®
( E lectronic S tability P rogram)
( Y
page 67) R
EBD ( E lectronic B rake force D istribution)
( Y
page 69) R
ADAPTIVE BRAKE ( Y
page 69)R
Active Brake Assist with cross-traffic function
( Y
page 69) R
STEER CONTROL ( Y
page 72)
Important safety notes If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override
the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt
your driving style to suit the prevailing road and
weather conditions and maintain a safe distance
from the vehicle in front. Drive carefully.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Pay particular attention to the informa-
tion regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and tires"
section ( Y
page 346).
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible. ABS (Anti-lock Braking System)
General information ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when
braking.
The % ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you
only brake gently.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
G WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y
page 277) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 245).
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over. X
To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving.Driving safety systems 63
Safety Z

Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on: R
Vehicles without the Offroad Engineering
package ( Y
page 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
At speeds below 20 mph (30 km/h), the front
wheels lock cyclically during braking. The dig-
ging-in effect achieved in the process reduces
the stopping distance on off-road terrain. This
limits steering capability.
BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
G WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. Active Brake Assist
General information
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and Adaptive Brake Assist.
Active Brake Assist can help you to minimize the
risk of a collision with the vehicle traveling in
front or reduce the effects of such a collision.
If Active Brake Assist detects that there is a risk
of collision, you will be warned visually and
acoustically. If you do not react to the visual and
audible collision warning, autonomous braking
can be initiated in critical situations. If you apply
the brake yourself in a critical situation, Adap-
tive Brake Assist of the Active Brake Assist sys-
tem supports you.
Important safety notes In particular, the detection of obstacles can be
impaired if: R
there is dirt on the sensors or anything else
covering the sensors R
there is snow or heavy rain R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garages R
a narrow vehicle is traveling in front, e.g. a
motorbike R
a vehicle is traveling in front on a different line R
new vehicles or after servicing is carried out
on the Active Brake Assist system
Observe the notes in the section on breaking-
in ( Y
page 137).
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
Activating/deactivating
Active Brake Assist is automatically active after
switching on the ignition.
You can activate or deactivate Active Brake
Assist ( Y
page 237) in the on-board computer.
When deactivated, the distance warning func-64
Driving safety systems
Safety

In appropriate driving situations, activate the
offroad program: X
Vehicles without the Offroad Engineering
package ( Y
page 217)X
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
Offroad 4ETS (Electronic Traction Sys-
tem) An ETS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated: R
Vehicles without the Offroad Engineering
package ( Y
page 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
Important safety notes
G WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Only operate the vehicle for a maximum of
ten seconds on a brake test dynamometer.
Switch off the ignition.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
! A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
ESP ®
is only deactivated if the

If activated in the multimedia system, the loca-
tor lighting also lights up in the dark (see sepa-
rate operating instructions). X
To open the tailgate automatically from
outside the vehicle: press and hold the T
button until the tailgate opens.
Vehicles with KEYLESS-GO: X
To close the tailgate automatically from
outside the vehicle: if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the T button on the SmartKey.
When the tailgate closes you can then release
the button.
KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a KEY-
LESS-GO key in the vehicle ( Y
page 140).
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
7 button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
KEYLESS-GO checks whether a valid SmartKey
is in the vehicle by periodically establishing a
radio connection between the vehicle and the
SmartKey. This happens: R
when starting the engine R
while driving R
when the external door handles are touched R
during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle. X
To lock the vehicle: touch sensor surface C
or D .
Make sure that you do not touch the inner
surface of the door handle. X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience closing
feature ( Y
page 87).
If you pull on the handle of the tailgate, only the
cargo compartment of the vehicle is unlocked.
Deactivating and activating If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby
conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby. X
To deactivate: press the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, KEY-
LESS-GO is deactivated ( Y
page 77).X
To activate: press any button on the Smart-
Key.
or X
Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again. SmartKey 75
Opening and closing Z

Problem
Possible causes/consequences and P Solutions
There is interference from a powerful source of radio waves. X
Unlock ( Y
page 81) or lock ( Y
page 81) the vehicle using the
mechanical key.
KEYLESS-GO is malfunctioning. X
Lock/unlock the vehicle using the remote control function of the
SmartKey. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function: X
Unlock ( Y
page 81) or lock ( Y
page 81) the vehicle using the
mechanical key. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 338).
or X
Jump-start the vehicle ( Y
page 338).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 77) and replace it if necessary
( Y
page 77).
If this does not work: X
Start your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves. X
Start your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well. SmartKey 79
Opening and closing Z

Problems with the windshield wipers Problem
Possible causes/consequences and P Solutions
The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield wiper
movement. The wiper motor has been deactivated. X
For safety reasons, you should remove the SmartKey from the igni-
tion lock.
or X
Switch off the engine using the Start/Stop button and open the
driver's door. X
Remove the cause of the obstruction. X
Switch the windshield wipers back on.
The windshield wipers
fail completely. The windshield wiper drive is malfunctioning. X
Select another wiper speed on the combination switch. X
Have the windshield wipers checked at a qualified specialist work-
shop.122
Windshield wipers
Lights and windshield wipers

! Do not warm up the engine with the vehicle
stationary. Drive off immediately. Avoid high
engine speeds and driving at full throttle until
the engine has reached its operating temper-
ature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles: at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold.
SmartKey positions
SmartKey
Z
To remove the SmartKeyG
Power supply for some consumers, such as
the windshield wipersH
Ignition (power supply for all consumers)
and drive position
I
To start the engine
i The SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
KEYLESS-GO
General notes
Vehicles with KEYLESS-GO are equipped with a
SmartKey featuring an integrated KEYLESS-GO
function and a detachable Start/Stop button. A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example, when
starting the engine.
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different key
positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
To start the vehicle without actively using the
SmartKey: R
the Start/Stop button must be inserted in the
ignition lock. R
the SmartKey must be in the vehicle. R
the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Y
page 75).
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can impair the functionality of the KEY-
LESS-GO key.
Do not keep the KEYLESS-GO key in the tem-
perature-controlled cup holder ( Y
page 303).
Otherwise, the KEYLESS-GO key will not be rec-
ognized.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time: R
you will not be able to switch on the ignition
with the Start/Stop button. R
you will not be able to start the engine with the
Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the button
on the front door ( Y
page 80), you can continue
to start the engine with the Start/Stop button.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.138
Driving
Driving and parking

ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes Vehicles with a gasoline engine: the catalytic
converter is preheated for up to 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission X
Shift the transmission to position P
( Y
page 146).
The transmission position display in the mul-
tifunction display shows P ( Y
page 148).
i You can start the engine in transmission
position P and N .
Starting procedure with the SmartKey X
To start a diesel engine : turn the SmartKey
to position 2 in the ignition lock ( Y
page 138).
The \( preglow indicator lamp in the instru-
ment cluster lights up. X
Turn the SmartKey to position 3 in the ignition
lock and release it as soon as the engine is
running ( Y
page 138).
i Vehicles with a diesel engine: you can
start the engine without preglow if the engine
is warm.
Using KEYLESS-GO to start the engine The Start/Stop button can be used to start the
vehicle without inserting the SmartKey into the
ignition lock. The Start/Stop button must be
inserted in the ignition lock and the SmartKey
must be in the vehicle. This mode for starting the
engine operates independently of the ECO
start/stop automatic engine start function. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 138).
Vehicles with a gasoline engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine ( Y
page 139).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the
previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where
your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
insert the SmartKey into the ignition lock, you
can carry out two more starting attempts.
Once you have started the engine, you can
switch the engine off via your smartphone at any
time.
You can only start the engine via your smart-
phone if: R
the SmartKey is in the ignition lock R
park position P is selected R
the accelerator pedal is not depressed R
the anti-theft alarm system is not activated R
the panic alarm is not activated R
the hazard warning lamps are switched off R
the hood is closed. R
the doors are closed and locked R
the windows and sliding sunroof are closed
Also make sure that: R
the fuel tank is sufficiently filled R
the starter battery is sufficiently charged140
Driving
Driving and parking