Battery MERCEDES-BENZ C320 2003 W203 Owner's Guide

262 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
-
ABS SYSTEM
VISIT WORKSHOP!
The ABS has detected a malfunction and
has switched off. The ESP and the BAS
are also deactivated. The brake system is
still functioning normally but without the
ABS available.

Continue driving with added caution.
Wheels will lock in hard braking
reducing steering capability.

Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
DISPLAY DEFECTIVE
VISIT WORKSHOP!
The ABS or the ABS display is
malfunctioning.

Continue driving with added caution.
Wheels will lock in hard braking
reducing steering capability.

Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
BAS
BRAKE ASSIST
NOT AVAILABLE!
The charging voltage has fallen below ten
volts and the BAS has switched off.

When the voltage is above this value
again, the BAS is operational again.

If necessary, have the generator and
battery checked.

263 Practical hints
What to do if …
BAS
BRAKE ASSIST
VISIT WORKSHOP!
The BAS has detected a malfunction and
switched off. The brake system is still
functioning normally but without the BAS
available.

Continue driving with added caution.

Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
DISPLAY DEFECTIVE
VISIT WORKSHOP!
The BAS or the BAS display is
malfunctioning.

Continue driving with added caution.

Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
#
BATTERY/ALTERNATOR
VISIT WORKSHOP!
The battery was charged with a battery
charger or jump started.

Have the battery checked at a service
station.
Display
Possible cause
Suggested solution

264 Practical hintsWhat to do if …#
BATTERY/ALTERNATOR
VISIT WORKSHOP!
The battery is no longer charging.
Possible causes:

alternator malfunctioning


broken poly-V-belt

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.
!
(Canada
only)
;
(USA only)
PARKING BRAKE
RELEASE PARKING BRAKE!
You are driving with the parking brake
set.

Release the parking brake
(page 51).
Display
Possible cause
Suggested solution

269 Practical hints
What to do if …
ESP
ESP
NOT AVAILABLE!
The ESP is deactivated because of a
malfunction or interrupted power supply.
The ABS might not be operational.

With vehicle stationary and the engine
running, turn the steering wheel
completely to the left and then to the
right to synchronize the ESP.
If the ESP message does not go out:

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions
increases the risk of accident.
The self-diagnosis has not been
completed.
The display will clear itself after driving a
short distance at more than 12 mph
(20 km/h).
The charging voltage has fallen below ten
volts and the ESP has switched off.

When the voltage is above this value
again, the ESP is operational again.

If necessary, have the generator and
battery checked.
Display
Possible cause
Suggested solution

278 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
#
UNDERVOLTAGE
ENGINE ON!
The battery has insufficient voltage and
can no longer supply the convenience
functions such as seat heater*.

Start the engine (
page 44).
UNDERVOLTAGE
SWITCH CONSUMERS OFF!
The battery is malfunctioning.

Have the battery checked at a service
station.
G
VISIT WORKSHOP!
DISPLAY DEFECTIVE
The instrument cluster display is
malfunctioning.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
±
VISIT WORKSHOP!
DISPLAY DEFECTIVE
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:

Coolant temperature display


Tachometer


Cruise control display

Have the electronic systems checked
by an authorized Mercedes-Benz
Center (
page 259).
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about
1/3
of total reservoir capacity.
Add washer fluid (
page 241).

286 Practical hintsUnlocking/locking in an emergencyLocking the vehicle
If you are unable to lock the vehicle with
the SmartKey, lock it with the mechanical
key as follows:
Close the passenger doors and the
trunk.

Press the central locking switch in the
cockpit (
page 92).

Check to see whether the locking
knobs on the passenger doors are still
visible. If necessary push them down
manually.

Lock the driver’s door with the me-
chanical key (
page 285).

Check if the trunk is locked. If neces-
sary lock the trunk with the mechanical
key (
page 90).
Changing batteries
If the batteries in the SmartKey are dis-
charged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an autho-
rized 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.Warning!
G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help
immediately.
iWhen changing batteries, always re-
place both batteries.
The required replacement batteries are
available at any Mercedes-Benz
Center.

287 Practical hints
Unlocking/locking in an emergency
SmartKey
1Mechanical key
2Battery compartment
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key1
(page 285).

Insert the mechanical key in side open-
ing and push gray slide.
The battery compartment2 is un-
latched.

Pull the battery compartment2 out of
the key housing in direction of arrow.3Battery
4Contact spring

Remove the batteries.

Using a lint-free cloth, insert new bat-
teries under the contact spring with the
plus (+) side facing up.

Return battery compartment into hous-
ing until it locks into place.
Fuel filler flap
Open trunk lid.

Fold away right-side tail lamp trim.

Reach inside through opening2.

Turn release knob1 clockwise (arrow).
The fuel filler flap can now be opened.

303 Practical hints
Battery
Battery
The battery is located in the engine com-
partment on the right hand side.
Removal of filter box:
Release the three clamps1.

Remove filter box.
Installation of filter box:

Insert filter box properly.

Secure it with the three clamps1.
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
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 key is in the starter switch. Oth-
erwise the alternator and other elec-
tronic components could be severely
damaged.
Have the battery checked regularly by
an authorized Mercedes-Benz Center.
Refer to Service Booklet for mainte-
nance intervals or contact your autho-
rized 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.

304 Practical hintsBattery1Negative terminal
2Positive terminal cover
Disconnecting the battery
Turn off all electrical consumers.

Open the hood (
page 235).

Remove the filter box.

Disconnect the battery negative
lead1.

Remove the cover2 from the positive
terminal.

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

Remove the battery bracket.

Take out the battery.
Charging and reinstalling the battery
Charge battery in accordance with the
instructions of the battery charger
manufacturer.

Reinstall the charged battery. Follow
the previously described steps in re-
verse order.
Warning!
G
With a disconnected battery

y o u w i l l n o l o n g e r b e a b l e t o t u r n t h e k e y
in the starter switch will have no effect


the selector lever will remain locked in
positionP
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.

305 Practical hints
Battery
Reconnecting the battery
Turn off all electrical consumers.

Connect the positive lead and fasten its
cover.

Connect the negative lead.

Reinstall the filter box (
page 303).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.
!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 reconnec-
tion):

Set the clock (
page 120)
Vehicles with COMAND*:
see COMAND operator’s manual.


Resynchronize the front seat head
restraints (
page 94).


Resynchronize the ESP
(page 75).


Resynchronize side windows
(page 189).


Resynchronize sliding/pop-up
roof* (
page 191).