2007 MERCEDES-BENZ C230 key battery

98 Controls in detail
Locking and unlocking
Trunk emergency release
With the emergency release button, the
trunk can be opened from inside the trunk.
The emergency release button is located
on the inside of the trunk lid.
1Emergency release button
Briefly press emergency release
button1.
The trunk unlocks and the trunk lid
opens.Illumination of the emergency release
button:

The button flashes 30 minutes after
opening the trunk.

The button flashes 60 minutes after
closing the trunk.
Be especially careful when small children
are around.
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it
with you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. A child’s
unsupervised access to a vehicle could
result in an accident and/or serious
personal injury.
Warning!G
Only drive with the trunk closed as, among
other dangers such as a blocked visibility,
exhaust fumes may enter the vehicle
interior.
iDo not place the SmartKey in the open
trunk. You may lock yourself out.
iIf the vehicle was previously centrally
locked, the trunk will lock automatically after
closing it. The turn signals will flash three times
to confirm locking.
!The trunk lid swings open upwards
automatically.
iThe emergency release button unlocks and
opens the trunk while the vehicle is standing still
or in motion.
iThe emergency release button does not
open the trunk lid if the vehicle battery is dis-
charged or disconnected.
iIf the vehicle has previously been locked
with the SmartKey, opening the trunk from the
inside using the emergency release button will
trigger the anti-theft alarm system*.
To cancel the alarm, do one of the following:

Press buttonŒ or‹ on the
SmartKey.

Insert the SmartKey in the starter switch.


116 Controls in detail
Lighting
Interior lighting
The controls are located in the overhead
control panel.
1Rear interior lighting on/off
2Right front reading lamp on/off
3Rocker switch for automatic control
system
4Left front reading lamp on/offDeactivating automatic control
Press the= symbol on rocker
switch3.
The interior lighting remains switched
off in darkness, even when you

unlock the vehicle

remove the SmartKey from the
starter switch

open a door

open the trunkActivating automatic control
Press rocker switch3 to center
position.
The interior lighting switch on in
darkness, when you

unlock the vehicle

remove the SmartKey from the
starter switch

open a door

open the trunk
The interior lighting switches off after ap-
proximately 10 seconds, see “Setting inte-
rior lighting delayed shut-off”
(
page 142).
!An interior lamp switched on manually does
not go out automatically.
Leaving an interior lamp switch in the ON posi-
tion for extended periods of time with the engine
turned off could result in a discharged battery.
iThe interior lighting is factory-set to auto-
matic mode.
iIf a door remains open, the interior lighting
switches off automatically after approximately
5minutes.

245 Controls in detail
Useful features
Please note that these functions are only
available with Mercedes-Benz approved
mobile phones. Please contact an
authorized Mercedes-Benz Center for in-
formation on features available for your
mobile phone of choice.
The cradle is located in the front center
armrest.
Open telephone tray (page 238).
Inserting mobile phone in mobile phone
cradle
Once the mobile phone has been inserted
in the mobile phone cradle, you have to
use the hands-free device to respond dur-
ing phone calls.
If applicable, remove the cover for the
external antenna connection from the
back of the mobile phone and store it in
a s a f e p l a c e . B e s u r e t o c o m p l y w i t h t h e
mobile phone’s operating instructions
as well.
Example illustration
1Insert the mobile phone
2Connector contact
3Mobile phone cradle
Slide the lower end of the mobile phone
into connector contact 2 on
cradle3.
Push the top of the mobile phone in di-
rection of arrow 1, until the lug on the
mobile phone release button engages.
The mobile phone is connected to the
network via the external antenna.
The mobile phone is linked to the
hands-free device and the multifunc-
tion steering wheel.
The battery is charged depending on its
charge status and the position of the
SmartKey in the starter switch. The
charge procedure will be indicated in
the mobile phone’s display.
You can place or receive phone calls. You
can control other functions of the mobile
phone via the control system
(
page 146), audio system (page 208),
COMAND* (see separate operating
instructions). !Do not try to remove the mobile phone along
with the cradle. You could otherwise damage the
mobile phone cradle.
iWhen you take the SmartKey out of the
starter switch, the mobile phone remains
switched on for approx. 10 minutes. If you place
or receive a call during this time, the mobile
phone switches off 10 minutes after the call has
been completed.

321 Practical hints
What to do if …
Where will I find ...?
Unlocking/locking in an emergency
Opening/closing in an emergency
Resetting activated head restraints
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Battery
Jump starting
Towing the vehicle
Fuses

366 Practical hints
Replacing SmartKey batteries
If the batteries in the SmartKey are
discharged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an
authorized Mercedes-Benz Center.
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.SmartKey
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key from the
SmartKey (
page 361).
1Mechanical key
2Battery compartment
Insert mechanical key1 into the
opening.
Press mechanical key1 in direction of
arrow.
The battery compartment2 is un-
latched.
Pull battery compartment2 out of the
housing.
3Batteries
4Contact spring
Remove the batteries3.
Using a lint-free cloth, insert new
batteries3 under the contact
springs4 with the positive terminal
(+) side facing up.
Return battery compartment2 into
housing until it locks into place.
Slide mechanical key 1 back into the
SmartKey.
Check the operation of the SmartKey.
Warning!G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help
immediately.
iWhen inserting the batteries, make sure
they are clean and free of lint.
iWhen replacing batteries, always replace
both batteries of both SmartKeys.
The required replacement batteries are available
at any Mercedes-Benz Center.

383 Practical hints
Battery
Battery
The battery is located in the engine
compartment on the right hand side.
1Clamps
Removing filter box:
Release clamps1.
Remove filter box.
Installing filter box:
Insert filter box properly.
Secure it with clamps1.
Warning!G
Failure to follow these instructions can
result in severe injury or death.
Observe all safety instructions and
precautions when handling automotive
batteries (
page 279).
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
!Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact an authorized
Mercedes-Benz Center for further information.

384 Practical hints
Battery
2Negative terminal
3Positive terminal cover
Disconnecting the battery
Apply the parking brake (page 54).
Make sure the gear selector lever* is
set to positionP (
page 153) (manual
transmission: to Neutral (
page 149)).
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Open the hood (page 274).
Remove the filter box (page 383).
Read and observe safety instructions
and precautions (
page 279) and
(
page 383).
Disconnect the battery negative lead
from negative terminal2.
Remove cover3 from the positive
terminal.
Disconnect the battery positive lead.
Removing the battery
Remove the screw-nuts securing the
battery.
Remove the battery bracket.
Pull out the battery ventilation hose
from the battery (depending on battery
arrangement in your vehicle model, the
ventilation hose is located either on the
left or right side of the battery).
Take out the battery.
Warning!G
With a disconnected battery

you will no longer be able to turn the
SmartKey in the starter switch

automatic transmission*: the gear se-
lector lever will remain locked in
positionP
!Always disconnect the battery in the order
described below. Otherwise the vehicle’s
electronics can be damaged.

385 Practical hints
Battery
Charging and reinstalling the batteryCharge battery in accordance with the
instructions of the battery charger
manufacturer.
Reinstall the charged battery. Follow
the previously described steps in
reverse order.
Reconnecting the battery
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Connect the battery positive lead and
fasten its cover3 (
page 384).
Connect the battery negative lead2
(
page 384).
Reinstall the filter box (page 383).Batteries contain materials that can harm
the environment if disposed of improperly.
Large 12 volt storage batteries contain
lead. Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
Warning!G
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available, permitting the charging of the bat-
tery in its installed position. Contact an au-
thorized Mercedes-Benz Center for
information and availability. Charge battery
in accordance with the separate instruc-
tions for the accessory battery charger.
!The battery, its filler caps and the battery
ventilation hose must always be securely in-
stalled when the vehicle is in operation.
!Always connect the battery in the order de-
scribed below. Otherwise the vehicle’s electron-
ics can be damaged.
!Never invert the terminal connections!
iThe following procedures must be carried
out following any interruption of battery power
(e.g. due to reconnection):

Set the clock (page 136).
Vehicles with COMAND*:
See COMAND operator’s manual.

Synchronize side windows (page 222).

Synchronize tilt/sliding sunroof*
(
page 226).