2017 MERCEDES-BENZ GLS check engine light

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

Problem
Possible causes/consequences and P Solutions
Vehicles with a gasoline
engine:
The engine is not running
smoothly and is misfir-
ing. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system. X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it. X
Have the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
gage shows a value
above 248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently. X
Stop as soon as possible and allow the engine and the coolant to
cool down. X
Check the coolant level ( Y
page 322). Observe the warning notes
as you do so and add coolant if necessary.
DYNAMIC SELECT controller Use the DYNAMIC SELECT controller to change
the drive program. Depending on the drive pro-
gram selected the following vehicle character-
istics will change: R
the drive (engine and transmission manage-
ment) R
the transmission R
the suspension R
the steering R
the availability of the ECO start/stop function
Each time you start the engine with the Smart-
Key or the Start/Stop button, the Comfort drive
program is activated. For further information
about starting the engine, see ( Y
page 139).
X
All vehicles (except Mercedes-AMG vehi-
cles): turn DYNAMIC SELECT controller C as many times as necessary until the desired
drive program is selected.
The selected drive program appears in the
multifunction display. After five seconds the
display goes out.
In addition, the current drive program settings
are displayed in the multimedia system dis-
play.
Drive programs available (all vehicles
except Mercedes-AMG vehicles):
Individual
Individual settings
Sport
Sporty driving characteris-
tics
Comfort
Comfortable and economi-
cal driving characteristics
Slippery
Optimal driving characteris-
tics on slippery or snow-
covered roads
Off-road
Optimal driving characteris-
tics for easily negotiable off-
road terrain
Offroad Plus
(vehicles with
Off-Road Engi-
neering pack-
age) Optimal driving characteris-
tics for rough terrainDYNAMIC SELECT controller 145
Driving and parking Z

This helps you to avoid overheating the
brakes and wearing them out excessively.
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.
Do not depress the brake pedal continuously
while the vehicle is in motion, e.g. causing the
brakes to rub by constantly applying light pres-
sure to the pedal. This results in excessive and
premature wear to the brake pads.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients. This is especially
important if the vehicle is laden.
This also applies if you have activated cruise
control, the speed limiter or Distance Pilot
DISTRONIC.
This will use the braking effect of the engine, so
that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly.
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 then 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
Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so. 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.
! A function or performance test should only
be carried out on a 2-axle dynamometer. If
you wish to operate the vehicle on such a
dynamometer, please consult a qualified spe-
cialist workshop in advance. You could oth-
erwise damage the drive train or the brake
system.
! Because ESP ®
is an automatic system, the
engine and ignition must be switched off
(SmartKey in position 0 or 1 or Start/Stop
button in position 0 or 1 ) when the electricDriving tips 165
Driving and parking Z

R
LOW RANGE offroad gear (vehicles with the
Offroad Engineering package) ( Y
page 219)R
Differential lock (vehicles with the Off-Road
Engineering package) ( Y
page 218)R
Off-road ABS ( Y
page 64)R
Off-road 4ETS ( Y
page 67)R
Off-road ESP ®
( Y
page 68)R
AIRMATIC package (vehicle level)
( Y
page 186) R
DSR (Downhill Speed Regulation)
( Y
page 216)
Observe the following notes: R
Stop the vehicle before starting to drive along
an off-road route. If necessary, select the off-
road program ( Y
page 218) or shift to the
LOW RANGE off-road gear ( Y
page 219).R
Select a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make
sure there is always sufficient ground clear-
ance. R
Check that items of luggage and loads are
stowed safely and are well secured
( Y
page 299). R
Always keep the engine running and in gear
when driving on a downhill gradient. Activate
DSR ( Y
page 216).R
Always keep the engine running and in gear
when driving on a slope. R
Adapt your speed to the terrain. The rougher,
steeper or more ruts on the terrain, the slower
your speed should be. R
Do not jump with the vehicle as this will inter-
rupt the vehicle's propulsion. R
Drive with extreme care on unfamiliar off-road
routes where visibility is poor. For safety rea-
sons, get out of the vehicle first and survey
the off-road route. R
Look out for obstacles, such as rocks, holes,
tree stumps and furrows. R
Always keep the doors, the tailgate, the side
windows and the sliding sunroof closed while
the vehicle is in motion. R
Do not shift the automatic transmission to
transmission position N .R
Observe the notes on off-road fording
( Y
page 167).
i Do not use the HOLD function when driving
off-road, on steep uphill or downhill gradients
or on slippery or loose surfaces. The HOLD function cannot hold the vehicle on such sur-
faces.
Checklist before driving off-road
! If the engine oil warning lamp lights up while
the vehicle is in motion, stop the vehicle in a
safe place as soon as possible. Check the
engine oil level. The engine oil warning lamp
warning must not be ignored. Continuing the
journey while the symbol is displayed could
lead to engine damage. X
Engine oil level: check the engine oil level
and add oil if necessary.
When driving on steep gradients, the engine
oil level must be sufficiently high to ensure a
correct oil supply in the vehicle. X
DEF tank (BlueTEC vehicles): check the
level and add if necessary ( Y
page 156).X
Tire-changing tool kit: check that the jack is
working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle. X
Wheels and tires: check the tire tread depth
and tire pressure. X
Check for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires. X
Replace any missing valve caps. X
Replace dented or damaged wheels. X
Rims: dented or bent rims can result in a loss
of tire pressure and damage the tire bead.
Before driving off-road, check the wheels and
replace them if necessary.
Checklist after driving off-road
! If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist work-
shop.
Driving over rough terrain places greater
demands on your vehicle than driving on normal
roads. After driving off-road, check the vehicle.
This allows you to detect damage promptly and
reduce the risk of an accident to yourself and
other road users. X
If the Offroad or Offroad Plus drive program
is selected: select the Individual , Sport ,Driving tips 169
Driving and parking Z

Comfort or Slippery drive program
( Y
page 145).X
Deactivate the LOW RANGE off-road gear
( Y
page 219).X
Deactivate DSR ( Y
page 216).X
Lower the vehicle level again to a level suita-
ble to the road conditions, e.g. to the normal
level. X
Clean the headlamps and rear lights and
check for damage. X
Clean the front and rear license plates. X
Clean the wheels and tires with a water jet
and remove any foreign objects. X
Clean the wheels, wheel housings and the
vehicle underside with a water jet; check for
any foreign objects and damage. X
Check whether twigs or other parts of plants
have become trapped. These increase the risk
of fire and can damage fuel pipes, brake
hoses or the rubber bellows of the axle joints
and propeller shafts. X
After the trip, examine without fail the entire
undercarriage, wheels, tires, brakes, body-
work structure, steering, chassis and exhaust
system for damage. X
After driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned. X
If you detect strong vibrations after off-road
travel, check for foreign objects in the wheels
and drive train and remove them if necessary.
Foreign objects can disturb the balance and
cause vibrations.
Driving on sand Observe the following rules when driving on
sand: R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217).R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218).R
Select a higher vehicle level. R
Avoid high engine speeds. R
Use the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate to
the terrain. R
Drive quickly to overcome the rolling resist-
ance. Otherwise the vehicle's wheels could
become stuck in loose ground. R
Drive in the tracks of other vehicles if possi-
ble. Make sure that: -
the tire ruts are not too deep. -
the sand is sufficiently firm. -
the ground clearance of the vehicle is suf-
ficient.
Tire ruts and gravel roads
! Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged or
bottom out and get stuck.
Observe the following rules when driving along
ruts in off-road terrain or on roads with loose
gravel: R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217). R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218). R
Select a higher vehicle level. R
Avoid high engine speeds. R
Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter. R
Drive slowly. R
Where ruts are too deep, drive with the
wheels of one side on the center grassy area,
if possible.
Driving over obstacles
! Obstacles could damage the floor of the
vehicle or components of the chassis. Ask
passengers for guidance when driving over
large obstacles. The passenger should always
keep a safe distance from the vehicle when
doing so in order to avoid injury as a result of
unexpected vehicle movements. After driving
off-road or over obstacles, check the vehicle
for possible damage, especially to the under-
body and the components of the chassis.170
Driving tips
Driving and parking

Observe the following rules when driving over
tree stumps, large stones and other obstacles: R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217). R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218). R
Select LOW RANGE offroad gear (vehicles
with Off-Road Engineering package)
( Y
page 219) R
Raise the vehicle level. R
Avoid high engine speeds. R
Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter. R
Drive very slowly. R
Drive straight over the center of obstacles.
Traveling uphill
Approach/departure angle
G WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is a
risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle. R
Observe the rules on off-road driving. R
Do not drive at an angle on slopes, inclines or
gradients, but instead follow the direct line of
fall. R
When driving down an incline, make use of the
engine's braking effect. Observe the engine
speed; do not overrev the engine. R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217). R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218). R
Before driving on extreme uphill and downhill
gradients, select the LOW RANGE offroad
gear (vehicles with Off-Road Engineering
package) ( Y
page 219). R
Drive slowly. R
Avoid high engine speeds. Drive at appropri-
ate engine speeds (maximum 3,000 rpm). R
Use the left-hand steering wheel paddle
shifter to shift into a lower gear in good time
on long and steep downhill gradients. R
Check the brakes after prolonged off-road
driving.
Hill start assist will aid you when pulling away on
a hill. For further information about hill start
assist, see ( Y
page 141).
Do not switch to transmission position N when
driving off-road. If you try to brake the vehicle
using the service brake, you could lose control
of the vehicle. If the gradient is too steep for your
vehicle, drive back down in reverse gear.
Always observe the approach/departure angle
values ( Y
page 386).
Maximum gradient-climbing capability Always observe the maximum gradient climbing
ability values ( Y
page 386).
Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator immediately
before reaching the brow of the hill. Make use of
the vehicle's own impetus to travel over the
brow.
This style of driving prevents: R
the vehicle from lifting off the ground on the
brow of a hill R
the vehicle from traveling too quickly down
the other side Driving tips 171
Driving and parking Z

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 indicator lamp lights up yellow in
the exterior mirrors and the Blind Spot
Assist Not Available When Towing a
Trailer See Operator's Manual message
appears in the multifunction display.
i You can deactivate the indicator lamps in
the exterior mirrors.
To do so, switch off Blind Spot Assist when: R
the SmartKey is in position 2 in the ignition
lock R
the engine is not running
Lane Keeping Assist General notes
C
Lane Keeping Assist camera
Lane Keeping Assist monitors the area in front of
your vehicle with camera C , which is mounted
at the top of the windshield. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
A warning may be given if a front wheel passes
over a lane marking. It will warn you by means of
intermittent vibration in the steering wheel for
up to 1.5 second s.
Im portant safety notes
G WARNING
Lane Keeping Assist may not always clearly
recognize lane markings. In this case, Lane Keeping Assist may: R
give an unnecessary warning R
not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist.
G WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is
a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-
ing Assist.
If you fail to adapt your driving style, Lane Keep-
ing Assist can neither reduce the risk of an acci-
dent nor override the laws of physics. Lane
Keeping Assist cannot take into account the
road, traffic and weather conditions. Lane Keep-
ing Assist is merely an aid. You are responsible
for the distance to the vehicle in front, for vehi-
cle speed, for braking in good time and for stay-
ing in your lane.
The Lane Keeping Assist does not keep the vehi-
cle in the lane.
The system may be impaired or may not function
if: R
there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray R
there is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet) R
the windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the camera R
there are no, several or unclear lane markings
for a lane, e.g. in areas with road construction
work R
the lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow R
the distance to the vehicle in front is too small
a nd the lane markings thus cannot be detec-
ted R
the lane markings change quickly, e.g. lanes
branch off, cross one another or mergeDriving systems 209
Driving and parking Z

R
the LOW RANGE offroad gear is activated
(vehicles with the Offroad Engineering pack-
age). R
a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist X
Make sure that Active Blind Spot Assist is
activated in the on-board computer
( Y
page 238). X
Turn the SmartKey to position 2 in the ignition
lock.
Warning lamps C in the exterior mirrors light
up red for approximately 1.5 seconds an d
then turn yellow.
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. Active Blind Spot Assist is then deacti-
vated. The indicator lamp lights up yellow in the
exterior mirrors and the Active Blind Spot
Asst. Not Available When Towing a
Trailer See Operator's Manual message
appears in the multifunction display.
Active Lane Keeping Assist
General notes
Active Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunction
camera C at the top of the windshield. Various
different areas to the front, rear and side of your
vehicle are also monitored with the aid of the
radar sensor system. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally. If you do not react to the warning, a lane-correcting application of the brakes can
bring the vehicle back into the original lane.
This function is available in a speed range
between 40 mph and 120 mph (60 km/h and
200 km/h).
For Active Lane Keeping Assist to assist you
when driving, the radar sensor system must be
operational.
Important safety notes If you fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of
accident nor override the laws of physics. Active
Lane Keeping Assist cannot take into account
road, weather or traffic conditions. Active Lane
Keeping Assist is only an aid. You are responsi-
ble for the distance to the vehicle in front, for
vehicle speed, for braking in good time and for
staying in your lane.
Active Lane Ke eping Assist cannot continuously
ke
ep your vehicle in its lane.
G WARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can: R
give an unnecessary warning and then
make a course-correcting brake application
to the vehicle R
not give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention in a non-critical driv-
ing situation.
The system may be impaired or may not function
if: R
there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray R
there is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet) R
the windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the cameraDriving system s 213
Dr ivi ng an d parking Z