
i
It is only possible to move the DIRECT
SELECT lever to the desired position from
position Pif you depress the brake pedal.
Only then is the parking lock released.
i The vehicle locks centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at
any time.
You can also deactivate the automatic lock-
ing feature (Y page 107).
X Depress the brake pedal and keep it
depressed.
X Shift the transmission to position Dor R.
X Release the parking brake (Y page 91).
X Release the brake pedal.
X Carefully depress the accelerator pedal.
i Upshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
Hill start assist Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient.
It holds the vehicle for a short time after you
have removed your foot from the brake pedal.
This gives you time to move your foot from
the brake pedal to the accelerator pedal and
depress it before the vehicle begins to roll. G
Risk of accident
Never leave the vehicle when it is held by hill
start assist. After approximately one second,
hill start assist will no longer brake your vehi-
cle and it could roll away.
X Take your foot off the brake pedal.
i Once you have taken your foot off the
brake pedal, the vehicle is held for around
one second.
X Pull away. Hill start assist will not function if:
R you are pulling away on a level road or a
downhill gradient.
R the transmission is in position N.
R the vehicle is secured with the parking
brake.
R ESP ®
is malfunctioning. Parking
G
Risk of accident
Only remove the key from the ignition lock
when the vehicle is stationary, as you cannot
steer the vehicle with the key removed.
Never leave children unsupervised in the vehi-
cle. They could release the parking brake. This
could lead to a serious or fatal accident. G
Risk of fire
Make sure that the exhaust system does not
under any circumstances come into contact
with flammable materials such as dry grass or
petrol. The material could otherwise ignite
and set the vehicle on fire.
To ensure that the vehicle is secured against
rolling away unintentionally:
R the parking brake must be applied
R the transmission must be in position Pand
the ignition key must be removed
R on steep uphill or downhill gradients, turn
the front wheels towards the kerb 90
Driving and parkingControls
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i
If the bonnet can be raised slightly, it is
not properly engaged. Open it again and
close it with a little more force. Engine oil
Depending on driving style, the vehicle con-
sumes up to 0.8 l oil per 1,000 km. The oil
consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
Checking the engine oil level Before checking the engine oil level the fol-
lowing conditions for the vehicle should be
met:
R the vehicle should be parked on level
ground.
R the engine should be switched off for at
least five minutes if the engine is at normal
operating temperature.
R the engine should be switched off for at
least 30 minutes if the engine is not at
operating temperature (i.e. if you only start
the engine briefly).
Using the on-board computer*
i Only possible on the GL 450 CDI 4MATIC.
On all other models, a dipstick is used to
check the engine oil level (Y page 177).
X Make sure that the key is in position
2(Y page 63) in the ignition lock.
X Press the &or* button to select the
following message: The measurement takes a few seconds. You
will see one of the following messages in the
multi-function display:
R
Engine oil level OK
R Add 1.0 litre to reach max. oil
level
R Add 1.5 litres to reach max. oil
level
R Add 2.0 litres to reach max. oil
level
X Top up the oil if necessary (Y page 177).
Other messages in the multi-function dis-
play
If the engine is at normal operating tempera-
ture and there is too much oil, you will see the
following message:
Engine oil level
Reduce oil level
X Have excess oil siphoned off.
! There is a risk of damage to the engine or
the catalytic converter if there is excess oil
in the engine.
If the Turn on ignition to see engine
oil level message appears:
X Turn the key to position 2(Y page 63) in
the ignition lock.
You will see the following message if you have
not observed the required waiting period:
Observe waiting period
X Repeat the measurement after about five
minutes if the engine is at normal operating
temperature.
X Repeat the measurement after about
30 minutes if the engine is not at normal
operating temperature (if the engine was
only started briefly).
The following message appears if the engine
is running:
Engine oil level Not when engine on
X Switch off the engine and wait for five
minutes if the engine is at normal operating 176
Engine compartmentOperation
* optional
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temperature, or for about 30 minutes if the
engine is not at normal operating temper-
ature (if you had started the engine only
briefly), before measuring.
i If you wish to cancel the measurement,
press the *or& button on the multi-
function steering wheel.
Using the oil dipstick Vehicles with a petrol/diesel engine (example)
X Pull oil dipstick :out of the oil dipstick
tube.
X Wipe off oil dipstick :.
X Insert oil dipstick :into the oil dipstick
tube to the stop, and take it out again.
The oil level is correct if the level is between
the minimum mark =and maximum
mark ;.
X Top up the oil if necessary.
Topping up the engine oil H
Environmental note
When topping up the oil, take care not to spill
any. Oil must not be allowed to escape into
the soil or waterways. You would otherwise be
damaging the environment. Cap (example)
X
Turn cap :anti-clockwise and remove.
X Top up with the amount of oil required
(Y page 289).
i The difference in quantity between the
minimum mark and maximum mark is
approximately 2 litres.
! Do not add too much oil. If too much oil
is added and the oil level is above the max-
imum mark on the dipstick, the engine or
catalytic converter could be damaged.
Have excess oil siphoned off.
X Replace cap :on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
For further information on engine oil, see
(Y page 289). Coolant
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
X Turn the key to position 2(Y page 63) in
the ignition lock.
X Check the coolant temperature gauge in
the multi-function display. G
Risk of injury
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has Engine compartment
177Operation
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Display messages
Possible causes/consequences and
X
X Solutions 4 Engine
oil level
Stop car,
turn
engine off The oil level is too low. There is a risk of engine damage.
X
Pull over and stop the vehicle safely, paying attention to
road and traffic conditions.
X Switch off the engine.
X Top up the engine oil and check the level (Y page 176).4 Engine
oil level
Reduce
oil level
You have added too much engine oil
33
. There is a risk of dam-
age to the engine or to the catalytic converter.
X Siphon off excess engine oil until it is at the specified level.
Observe the legal requirements. 4 Engine
oil level
Consult
workshop The engine oil level has dropped to a critical level or the
measuring system is malfunctioning.
33
X Check the engine oil level ( Ypage 176).
If the engine oil level is OK:
X Visit a qualified specialist workshop.
If the engine oil level is not OK:
X Top up the engine oil.
X If the warning message disappears: consult a qualified spe-
cialist workshop.
X If the warning message does not disappear: keep the vehi-
cle at a standstill and notify a qualified specialist workshop. 4 Engine
oil level
cannot be
measured
The measuring system is malfunctioning
33
.
X Visit a qualified specialist workshop. h Tyre pres‐
sure Cau‐
tion,
tyre
defect
G
Risk of accident
The tyre pressure in one or more tyres has dropped suddenly.
The affected wheel is highlighted in the tyre pressure display
of the tyre pressure monitor*.
X Stop the vehicle without making any sudden steering or
braking manoeuvres. Pay attention to traffic conditions as
you do so.
X Repair the faulty tyre or replace the wheel ( Ypage 262). 33
Only for certain countries. Display
messages
229Practical advice
* optional
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Jump-start connection point
:
Earth point (negative terminal)
; Positive terminal (under the cover) Reconnecting the battery
! Always disconnect the battery in
the order described below. Never swap the
battery terminals. You may otherwise dam-
age the vehicle electronics.
X Switch off all electrical consumers (e.g.
radio, blower, etc.).
X Connect the positive terminal clamp and
secure the cover.
X Connect the negative terminal clamp.
X Connect the breather hose.
i If the battery power supply has been inter-
rupted (e.g. if it has been reconnected), you
must carry out the following tasks:
R set the time (Y page 104).
On vehicles with COMAND and a naviga-
tion system*, the clock is set automati-
cally.
R reset the sliding/tilting sun-
roof* (Y page 151).
R reset the function for folding the exterior
mirrors in/out automatically* by folding
the mirrors out once (Y page 73)
R reset the side windows ( Ypage 86). Jump-starting
If your vehicle's battery is discharged, the
engine can be jump-started from another
vehicle or from an external battery using jump
leads.
Observe the following points:
R you may only jump-start when the engine
and catalytic converter are cold.
R do not start the engine if the battery is fro-
zen. Let the battery thaw first.
R jump-starting may only be performed from
batteries with a nominal voltage of 12 V.
R only use jump leads which have a sufficient
cross-section and insulated terminal
clamps.
i Jump leads and further information about
jump-starting can be obtained from any
Mercedes-Benz Service Centre.
! Avoid repeated and lengthy starting
attempts.
Do not use a rapid-charging device to start
the engine. G
Risk of injury
There is a risk of acid burns when jump-start-
ing a vehicle due to the gases which escape
from the battery. Do not lean over the battery
while the engine is being jump-started. G
Risk of explosion
Gases escaping from the battery during jump-
starting may cause minor explosions. Avoid
creating sparks. Keep naked flames away
from the battery, and do not smoke.
Comply with safety precautions and take pro-
tective measures when handling batteries.
You will find these under "Battery" in the
index.
X Make sure that the two vehicles do not
touch.
X Depress the parking brake firmly. 276
Jump-startingPractical advice
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Low outside temperatures
AdBlue
®
freezes at a temperature of approx-
imately –11 †. The vehicle is equipped with
an AdBlue ®
preheating system at the factory.
Winter operation is therefore also guaranteed
at temperatures below –11 †.
Special additives !
Only use AdBlue ®
compliant with
ISO 22241. Do not add any special addi-
tives to AdBlue ®
and do not dilute it with
water. Doing so may destroy the BlueTEC
exhaust gas aftertreatment system.
Damage resulting from the use of such
additives or from water is not covered by
the Mercedes-Benz implied warranty.
Purity The purity of AdBlue
®
is particularly important
for avoiding malfunctions in the exhaust gas
aftertreatment system.
If AdBlue ®
is pumped out of the AdBlue ®
tank,
e.g. during repair work, it must not be
returned to the tank as the purity of the fluid
can no longer be guaranteed.
! Impurities in AdBlue ®
(e.g. due to other
service products, cleaning agents or dust) lead to increased emission values, system
malfunctions, catalytic converter damage
or damage to the BlueTEC system. Vehicle model Total capacity of
the AdBlue ®
tank GL 350 BlueTEC 31.7 l
Engine oil
Only Mercedes-Benz approved engine oils
may be used in Mercedes-Benz engines.
A list of the engine oils tested and approved
in accordance with the Mercedes-Benz Spec-
ifications for Service Products can be called
up by visiting http://bevo.daimler.com and
entering the MB Sheet number. Further infor-
mation on tested and approved engine oils
can be obtained from any Mercedes-Benz
Service Centre. Engine oils which have been
approved by Mercedes-Benz have the MB
Sheet number indicated on the oil container
under the "MB approval" notice. The table
shows which MB Sheet number applies to
which engine: GL 450 4MATIC
GL 500 4MATIC
MB Sheet number
229.3, 229.5 mmService products and capacities
289Technical data
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