2003 MERCEDES-BENZ E320 battery

305 Practical hints
What to do if …
2
Brake wear
Visit workshop!
The brake pads have reached their wear
limit.

Brake pad thickness must be visually
inspected at the intervals specified in
the Service Booklet.

Have the brake pads replaced as
soon as possible.
T
Brake malfunction
Stop vehicle
The SBC brake system is in the limp-home
(emergency operation) mode. Consider-
ably greater brake pedal force is required
and the stopping distance is increased.
Do not exceed a speed of 55 mph
(90 km/h).

Do not drive any further.

Significantly greater force must be
applied to the brake pedal.

Call for roadside assistance.
Except Canada:;Canada only:3
Reduced braking effect
Start engine!
Increased braking dis-
tance
Start engine!
The battery has insufficient voltage and
cannot supply sufficient power to the SBC
brake system.

Start the engine.
The message disappears when suffi-
cient voltage is available
Display
Possible cause
Suggested solution

309 Practical hints
What to do if …
Display
Possible cause
Suggested solution
F
Key
Check battery!
The batteries in the KEYLESS-GO*
key are discharged.

Change the batteries (
page 328).
Key
not recognized!
The KEYLESS-GO* key is not recog-
nized while the engine is running be-
cause

the card is not in the vehicle


there is strong radio-frequency
interference

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

Search for the card or continue to operate
the vehicle with the key.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started again
after the engine is stopped.
The KEYLESS-GO* key is momen-
tarily not recognized.

Change the position of the card in the vehi-
cle.

Operate the vehicle with the key if neces-
sary.
ì
Function
Not available!
This display appears if button ì
or í on the multifunction steer-
ing wheel is pressed and the vehicle
is not equipped with a telephone.

328 Practical hintsUnlocking/locking in an emergencyUnlocking the trunk
The trunk can no longer be locked with the
key.
Lock and unlock the trunk with the me-
chanical key as follows:Trunk lid lock1Unlocking
2Locking
Insert the mechanical key in the trunk
lid lock.

Turn the key to the left in position1
and hold it in this position.

Pull on the trunk lid handle and lift the
trunk lid.
Locking 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 100).

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 327).

Check if the trunk is locked. If neces-
sary lock the trunk with the mechanical
key (
page 98).
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.

329 Practical hints
Unlocking/locking in an emergency
SmartKey/SmartKey with KEY-
LESS-GO*
1Mechanical key
2Battery compartment
Replacement batteries: Lithium, type
CR 2025 or equivalent.

Remove mechanical key1
(page 327).

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

Pull 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 emergency release
1Release knob
Remove right-side tail trim.

Turn release knob1 clockwise (arrow).
The fuel filler flap can know be opened.
iWhen changing batteries, always re-
place both batteries.
The required replacement batteries are
available at any authorized
Mercedes-Benz Center.

343 Practical hints
Batteries
Batteries
Your vehicle is equipped with two batter-
ies:

Auxiliary battery (back-up battery; en-
ables vehicle to shut down electrical
systems in a controlled manner should
the main battery fail; auxiliary battery is
located in the engine compartment)


The main battery (battery for starter
and electrical consumers; located in
the trunk).The main battery is in the trunk under the
luggage box. Remove the luggage box
(
page 325).
Main battery in trunk1Negative terminal
2Positive terminalWarning!
G
Jump starting must only be done using the
main battery in the trunk.
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.

344 Practical hintsBatteries
Disconnecting the battery
Depress the parking brake firmly or
move the gear selector lever to
positionP.

Open the trunk (
page 261).

Disconnect battery negative lead1.

Remove cover2 from the positive ter-
minal.

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.
!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.
Contact your authorized
Mercedes-Benz Center for further infor-
mation.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.
Warning!
G
With a disconnected battery

the brake boosting effect is not avail-
able.
You need more power to brake and
brake pedal travel is increased. If neces-
sary, you must depress the brake pedal
with full power.


you can no longer turn the ignition key
or, in cars with KEYLESS-GO*, pressing
the KEY-LESS-GO button* on the gear
selector lever has no effect.


the gear selector lever is locked in
position P.

345 Practical hints
Batteries
Reconnecting the batteries
Turn off all electrical consumers.

Connect the positive lead and fasten its
cover.

Connect the negative lead.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 reconnec-
tion):

Set the clock (
page 136) (vehi-
cles with COMAND*: see COMAND
operator’s manual).


Resynchronize the front seat head
restraints (
page 104).


Resynchronize the ESP
(page 75).


Re-enter the radio code (see radio
operating instructions).


Resynchronize the side windows
(page 186).


Resynchronize the sliding/pop-up
roof* (
page 189).

346 Practical hintsJump 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.


Use only jumper cables with sufficient
cross-section, insulated terminal
clamps and polarity reversal protec-
tion.
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.
Read all instructions before proceeding.
iJumper cables with polarity reversal
protection are available at any autho-
rized Mercedes-Benz Center.
!Jump starting may only be performed
on the main battery installed in the
trunk.
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.
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.