
Changing the batteries
304 Resetting triggered NECK-PRO head
restraints
If the NECK-PRO head restraints are triggered
in an accident, you must reset the head
restraints on the driver's and front-passenger
seats. Otherwise, the additional protection
will not be available in the event of another
rear-end collision. You can recognise when
head restraints have been triggered by the
fact that they have been moved forwards and
can no longer be adjusted.
Mercedes-Benz recommends that you have
NECK-PRO head restraints checked at a quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre, following a rear-end
collision.
i This work requires a lot of strength. If you
have difficulty resetting the head
restraints, have this work carried out at a
qualified specialist workshop, e.g. a
Mercedes-Benz Service Centre. 1
To move forwards
2 To push down
3 To push back
X Move the top of the head restraint cushion
forwards in the direction of arrow 1.
X Push the head restraint cushion down in
the direction of arrow 2as far as it will go.
X Push the head restraint cushion firmly
backwards in the direction of arrow 3until
it engages.
X Repeat this procedure for the second head
restraint. Changing the batteries
Notes
It is advisable to have the batteries replaced
at a qualified specialist workshop, e.g. at a
Mercedes-Benz Service Centre. G
Risk of poisoning
Batteries contain toxic and caustic sub-
stances. For this reason, keep batteries
away from children.
If a battery is swallowed, consult a doctor
immediately. H
Environmental note
Do not dispose of batteries with the house-
hold rubbish. They contain highly toxic sub-
stances.
Take discharged batteries to a qualified
specialist workshop, e.g. a Mercedes-Benz
Service Centre, or to a special collection
point for old batteries. Practical advice
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Changing the batteries
305Key or KEYLESS GO key*
Checking the batteries X
Press the jork button.
The batteries are in order if the battery
charge indicator lamp lights up briefly.
Changing the batteries You require two CR 2025 3 V cell batteries.
X
Remove the emergency key element from
the key (Y page 302). 1
Emergency key element
2 Battery tray X
Insert emergency key element 1into the
opening in the key and push in the direction
of the arrow.
Battery tray 2is released.
X Pull battery tray 2out of the key. 1
Batteries
X Remove old batteries 1from the battery
tray.
X Insert the new batteries beneath the con-
tact spring with the positive terminal facing
upwards. Use a lint-free cloth to do so.
X Push the battery tray back into the key
housing until the battery tray engages.
X Check the function of all key buttons on the
vehicle. Auxiliary heating* remote control
One 6V pin battery, type 2CR11108 is
required. 1
Battery
2 Battery cover
X Prise apart the side arms of battery cover
2 and slide off battery cover 2.
X Remove old battery 1.
X Insert the new battery. Observe the polarity
signs on the back of the remote control
when doing so.
X Slide battery cover 2back onto the
remote control.
X Use the remote control to check the vehi-
cle's auxiliary heating functions. Practical advice
* optional
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Battery
323
You must not exceed a maximum speed of
80 km/h. G
Risk of accident
The handling characteristics of your vehicle
deteriorate in run-flat mode, for example:
R when cornering
R when braking
R when accelerating rapidly
Adapt your driving style accordingly and
avoid sudden changes in direction and sud-
den acceleration, as well as driving over
obstacles (i.e. kerbs, potholes), and driving
off-road. This is particularly the case when
the vehicle is heavily laden.
The maximum permissible distance that
can be driven in run-flat mode depends to
a large extent on the loads placed on the
vehicle. It can be shorter due to high
speeds, a heavy load, sudden acceleration
and/or manoeuvring, the road surface con-
dition, outside temperature, etc., or further
if you drive carefully and conservatively.
Do not continue to drive in run-flat mode if:
R you hear banging noises
R the vehicle starts to shake
R you see smoke and smell rubber R
ESP ®
is intervening constantly
R there are tears in the sidewalls of the tyre
After driving in run-flat mode, you must
have the rims checked for damage at a
qualified specialist workshop which has the
necessary specialist knowledge and tools
to carry out the work required. The faulty
tyre must be replaced in every case.
Mercedes-Benz recommends that you use
a Mercedes-Benz Service Centre for this
purpose. In particular, work relevant to
safety or on safety-related systems must be
carried out at a qualified specialist work-
shop.
i On a vehicle with MOExtended tyres, only
use MOExtended spare tyres. These must
be of the size specified for the vehicle. Battery
Notes on the vehicle battery
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period.
To prevent damage from corrosion, only
replace the battery with one that has a central
ventilation cover.
Consult a Mercedes-Benz Service Centre if
you wish to leave your vehicle parked up for
a long period of time. G
Risk of injury
Comply with safety precautions and take
protective measures when handling batter-
ies. Risk of explosion
Fire, naked flames and
smoking are prohibited
when handling the bat-
tery. Avoid creating
sparks. Practical advice
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Battery
324 Battery acid is caustic.
Avoid contact with the
skin, eyes or clothing.
Wear suitable protective
clothing, in particular
gloves, an apron and a
face mask.
Immediately rinse acid
splashes off with clean
water. Consult a doctor if
necessary.
Wear eye protection.
Keep children away.
Observe this Owner's
Manual.
H
Environmental note
Do not dispose of batteries with the house-
hold rubbish. Dispose of defective batteries
in an environmentally responsible manner.
Take them to a Mercedes-Benz Service Centre or to a special collection point for
old batteries.
G
Risk of injury
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which
have been tested and approved for your
vehicle by Mercedes-Benz. These batteries
provide increased impact protection to pre-
vent vehicle occupants from suffering acid
burns should the battery be damaged in the
event of an accident.
To prevent acid burns, observe the follow-
ing safety notes when handling batteries:
R Do not lean over batteries.
R Do not place any metal objects on a bat-
tery. You could otherwise cause a short
circuit and the battery's highly flammable
gas mixture could ignite.
R Make sure that you do not create an elec-
trostatic charge, e.g. by wearing syn-
thetic clothing or as a result of friction on
fabrics. Therefore, you should not pull or
slide the battery over carpets or other
synthetic materials.
R Never touch the battery first. To dis-
charge a possible electrostatic charge, step out of the vehicle first and touch the
bodywork.
R Do not wipe the battery using a cloth. The
battery may explode as a result of elec-
trostatic charge or due to flying sparks.
! Switch off the engine and remove the
key/KEYLESS GO * button before loosen-
ing or removing the battery terminal
clamps. You may otherwise destroy elec-
tronic components such as the alternator.
i Mercedes-Benz recommends that you
have all work involving the battery, e.g.
removing, charging and replacing, carried
out at a qualified specialist workshop, e.g.
a Mercedes-Benz Service Centre.
The battery is located under the front seat on
the right-hand side when viewed in the direc-
tion of travel. Practical advice
* optional
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Battery
325Disconnecting the battery
G
Risk of accident
If the battery is disconnected:
R the brake boosting effect will not be avail-
able. Greater braking force will then be
required and the brake pedal travel will
be longer. If necessary, depress the
brake pedal with maximum force.
R you can no longer turn the key in the igni-
tion and, on vehicles with KEYLESS
GO*, pressing the KEYLESS GO button*
will have no effect
R the selector lever is locked in position P
! Always disconnect the battery in
the order described below. Never swap the
terminal clamps. You may otherwise dam-
age the vehicle electronics.
X Firmly depress the parking brake and shift
the DIRECT SELECT lever to position P.
X Switch off the engine.
X Turn the key to position 2(Y page 76)in the
ignition lock.
X Switch off all electrical consumers. X
Open the front right-hand door.
X Position the right-hand front seat at its rear-
most position:
R
partially electric seat adjustment
(Y page 78)
R fully electric seat adjustment
(Y page 79) 1
Front right seat rail cover
2 Front left seat rail cover
X Pull right-hand cover 1forwards in the
direction of the arrow and pull it off the seat
rail.
X Pull left-hand cover 2as far forwards as
possible in the direction of the arrow.
i Left-hand cover 2cannot be completely
pulled off the seat rail. 3
Battery cover fastening nuts
X Loosen and remove fastening nuts 3
along the edge of the carpet.
i To do this, you need a 6 mm Allen key with
a shaft at least 30 cm long (not included in
the vehicle tool kit).
X Position the right-hand front seat as far
forward as possible:
R partially electric seat adjustment
(Y page 78)
R fully electric seat adjustment (Y page 79)
X Turn the key to position 0(Y page 76) in
the ignition lock. Practical advice
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Battery
326
X
Remove the key from the ignition lock.
or
X On vehicles with KEYLESS GO*: open the
driver's door. 4
Rear seat rail
5 Rear seat rail cover
X Prise off left-hand cover 5from seat rail
4.
X Repeat the procedure for right-hand cover
5. 6
Carpet
X Pull carpet 6back in the direction of the
arrow and fold it. 7
Battery cover fastening nuts X
Loosen and remove fastening nuts 7.
i To do this, you need a 6 mm Allen key with
a shaft at least 30 cm long (not included in
the vehicle tool kit). 8
Battery cover with integrated air duct
9 Pull battery cover to the side
a To raise the battery cover
X Raise battery cover 8gently in the direc-
tion of arrow aand pull in the direction of
arrow 9. Practical advice
* optional
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Battery
327b
Breather hose
c battery
d Battery holder
e Fastening nuts
X Remove breather hose bfrom battery
c.
X Loosen and remove fastening nuts e.
X Remove fastening d.
X Push battery cto the left. f
Positive terminal clamp
g Negative terminal clamp
X Disconnect negative terminal clamp g
from the battery and put it down so that it
does not touch positive terminal clamp
f.
X Remove the cover from positive terminal
clamp f.
X Remove positive terminal clamp ffrom
the battery. Removing the battery
X Disconnect the battery ( Ypage 325).
X Pull the battery up out of the recess. Charging and fitting the battery
G
Risk of injury
Only charge the battery in a well-ventilated
area. As the battery is being charged, gases
can escape and generate minor explosions.
This may injure you and other persons or
cause damage to the paintwork or acid cor-
rosion on the vehicle.
You can obtain information about battery
chargers which allow the battery to be
charged when still installed from a qualified
specialist workshop, e.g. a Mercedes-Benz
Service Centre. G
Risk of injury
There is a risk of acid burns during the
charging process due to the gases which
escape from the battery. Do not lean over
the battery during the charging process. G
Risk of injury
Battery acid is caustic. Avoid contact with
the skin, eyes or clothing. Practical advice
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Battery
328
!
Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery
chargers allow the battery to be charged
while it is still installed. Otherwise, the vehi-
cle's electronic system may be damaged.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
X Charge the battery. Observe the notes in
the operating instructions for your battery
charger.
X Refit the charged battery.
To do this, follow the steps described in
"Removing the battery" (Y page 327) in
reverse order.
i You can charge the battery using the
jump-start terminals. These are located on
the right when viewed in the direction of
travel.
X Open the bonnet (Y page 220). Jump-start terminals
1
Body earth point (negative terminal)
2 Positive terminal (under cover)
3 Cover Reconnecting the battery
! Always reconnect the battery in the
sequence described below. Never swap the
terminal clamps. You may otherwise dam-
age the vehicle electronics.
X Switch off all electrical consumers.
X Connect the positive terminal clamp and
secure the cover.
X Connect the negative terminal clamp.
X Connect the breather hose. Make sure that
a cell cap is fitted is fitted on the side. 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 132).
On vehicles with COMAND and a naviga-
tion system*, the clock is set automati-
cally
R Reset the sliding/tilting sun-
roof* (Y page 180).
R Reset the panorama sliding/tilting sun-
roof (Y page 183).
R Reset the function for folding the exterior
mirrors in/out automatically* by folding
the mirrors out once ( Ypage 91).
R Reset the side windows (Y page 107)Practical advice
* optional
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