2005 MERCEDES-BENZ CLK320 COUPE Battery

373 Practical hints
What to do if …?
Symbol messagesDisplay symbol
Display message
Possible cause
Possible solution
#
Visit Workshop!
The battery is no longer charging.
Possible causes:

broken poly-V-belt


alternator malfunctioning

Stop immediately and check the
poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise
the engine will overheat due to an
inoperative water pump which may
result in damage to the engine. Notify
an authorized Mercedes-Benz Center.
If it is intact:

Drive immediately to the nearest
authorized Mercedes-Benz Center.
Undervoltage
Charge battery
The battery has insufficient voltage.

Start the engine (
page 46).
Undervoltage
Switch off
consumers
The battery has insufficient voltage.

Turn off unnecessary electrical con-
sumers.

381 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
A
Reserve fuel
The fuel level has dropped below the re-
serve mark.

Refuel at the next gas station
(page 305).
Y
Hood open!
You are driving with the hood open.

Close the hood (
page 309).
I
Remove key
You have forgotten to remove the
SmartKey.

Remove the SmartKey from the start-
er switch.
Replace key
No additional code available for SmartKey
or SmartKey with KEYLESS-GO*

Visit an authorized Mercedes-Benz
Center as soon as possible.
Key
Check battery!
The SmartKey with KEYLESS-GO* batter-
ies are discharged.

Change the batteries (
page 402).
Key
not recognized!
The SmartKey with KEYLESS-GO* is not
recognized while the engine is running be-
cause

the SmartKey is not in the vehicle


there is strong radio-frequency inter-
ference

Stop the vehicle as soon as it is safe to
do so.

Search for the SmartKey.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started
again after the engine has been stopped.
The SmartKey with KEYLESS-GO* is mo-
mentarily not recognized.

Change the position of the SmartKey
in the vehicle.

Operate the vehicle with the SmartKey
in the starter switch if necessary.
Keyless Go
Check system
The KEYLESS-GO* system is malfunction-
ing.

Visit an authorized Mercedes-Benz
Center as soon as possible.

402 Practical hintsReplacing batteries in the SmartKey/SmartKey with KEYLESS-GO*If the batteries in the SmartKey or the
SmartKey with KEYLESS-GO* are dis-
charged, 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 mechanical key1
(page 397).
1Mechanical key
2Battery compartment

Insert mechanical key 1 in side
opening and push gray slide.
Battery compartment2 is unlatched.

Pull battery compartment 2 out of the
SmartKey housing in direction of
arrow.
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 changing batteries, always re-
place both batteries.
The required replacement batteries are
available at any Mercedes-Benz
Center.

403 Practical hints
Replacing batteries in the SmartKey/SmartKey with KEYLESS-GO*

Remove the batteries.
3Battery
4Contact spring

Using a lint-free cloth, insert new
batteries 3 under the contact
spring4 with the plus (+) side facing
up.

Return battery compartment 2 into
housing until it locks into place.

Slide mechanical key 1 back into the
SmartKey.

Check the operation of the SmartKey.
SmartKey with KEYLESS-GO*
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key (
page 397).

Insert the mechanical key in side open-
ing and push grey slide.
The battery compartment is unlatched.

Pull the battery compartment out of the
SmartKey housing.
1Battery
2Tilt battery up
3Mechanical key

Using mechanical key3, apply
pressure to position2.
Battery1 tilts up slightly.

Pull batteries1 out in direction of
arrow.

Using a lint-free cloth, insert new
batteries1 with the plus (+) side
facing up.

Return battery compartment into hous-
ing until it locks into place.

Slide mechanical key 3 back into the
SmartKey.

Check the operation of the SmartKey
and the KEYLESS-GO*.

420 Practical hintsBatteryThe 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 re-
sult in severe injury or death.
Observe all safety instructions and
precautions when handling automotive
batteries (
page 314).
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.
!Never loosen or detach battery termi-
nal clamps while the engine is running
or the SmartKey is in the starter switch.
Otherwise the alternator and other
electronic components could be se-
verely damaged.
Have the battery checked regularly by
an authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for
maintenance intervals or contact an
authorized Mercedes-Benz Center for
further information.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.

421 Practical hints
Battery
1Negative terminal
2Positive terminal cover
Disconnecting the battery
Turn off the engine (
page 46).

Turn off all electrical consumers.

Remove SmartKey from starter switch.
Vehicles with KEYLESS-GO*:
Press the start / stop button until
the engine shuts off.

Open the driver’s door.

Open the hood (
page 308).

Remove the filter box (
page 420).

Disconnect the battery negative lead
from negative terminal1.

Remove cover2 from the positive ter-
minal.

Disconnect the battery positive lead.
Removing the battery
Remove the screw securing the
battery.

Remove the battery support and
bracket.

Take out the battery.
Warning!
G
With a disconnected battery

you will no longer be able to turn the
SmartKey in the starter switch and
pressing the KEYLESS-GO* start/stop
button on the gear selector lever will
have no effect


the gear selector lever will remain
locked in positionP

422 Practical hintsBatteryCharging and reinstalling battery
Charge 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.
Vehicles with KEYLESS-GO*:
Press the start / stop button until
the engine shuts off.

Open the driver’s door.

Connect the battery positive lead and
fasten its cover 2.

Connect the battery negative lead.

Reinstall the filter box (
page 420).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. Gases may escape during charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
!NEVER invert the terminal connections!!The battery, its filler caps and the vent
tube must always be securely installed
when the vehicle is in operation.
iThe following procedures must be car-
ried out following any interruption of
battery power (e.g. due to reconnect-
ing):

Set the clock (
page 151) (vehi-
cles with COMAND*: see COMAND
operator’s manual).


Resynchronize the side windows
(page 250).


Resynchronize the tilt/sliding
sunroof* (
page 254).

423 Practical hints
Jump starting
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:

Jump starting should only be performed
when the engine and catalytic convert-
er are cold.


Do not start the engine if the battery is
frozen. Let the battery thaw out first.


Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a more powerful battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.


Only use jumper cables with sufficient
cross-section and insulated terminal
clamps.


Always make sure the jumper cables
are not on or near pulleys, fans or other
parts that move when an engine is
started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, 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 very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
!Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If the engine does not run after several
unsuccessful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter and
may present a fire risk.
Make sure the jumper cables do not
have loose or missing insulation.
Make sure the cable clamps do not
touch any other metal part while the
other end is still attached to a battery.