2008 MERCEDES-BENZ ML320 battery

427 Practical hints
What to do if …
Symbol messages
Display symbolDisplay messagePossible cause/consequencePossible solution
ò Replace air filter.The air filter is clogged.Have the air filter checked by an authorized
Mercedes-Benz Light Truck Center.
#The battery is no longer charging.
Possible causes:

alternator malfunctioning

broken poly-V-belt
Do not forget that the brake system
requires electrical energy and may be
operating with restricted capability.
Considerably greater brake pedal
force is required and the stopping dis-
tance is increased.
Stop the vehicle in a safe location or as soon as
it is safe to do so.
Apply the parking brake (page 65).
 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.
Contact an authorized Mercedes-Benz Light
Truck Center.
If it is intact:
Drive immediately to the nearest authorized
Mercedes-Benz Light Truck Center. Adjust
driving to be consistent with reduced braking
responsiveness.

428 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
#Battery / Alternator
Stop VehicleThe battery is defective.Stop the vehicle in a safe location or as
soon as it is safe to do so.
Apply the parking brake (page 65).
Do not continue to drive.
Contact an authorized Mercedes-Benz
Light Truck Center.
{InoperativeDownhill Speed Regulation is
malfunctioning.Have the Downhill Speed Regulation
checked by an authorized Mercedes-Benz
Light Truck Center.
2Brake WearThe brake pads have reached
their wear limit.Have the brake pads replaced as soon as
possible.
!Brake pad thickness must be visually in-
spected by a qualified technician at the intervals
specified in the Maintenance Booklet.

444 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
4Reserve FuelThe fuel level has gone below the reserve
mark.Refuel at the next gas station
(
page 337).
Ultra Low-sulfur
Diesel Fuel OnlyVehicles with diesel engine only:
The fuel level has gone below the reserve
mark.Refuel at the next gas station
(
page 337).
Only use commercially available
vehicular ULTRA-LOW SULFUR
HIGHWAY DIESEL FUEL
(15 ppm SULFUR MAXIMUM).
L Tele Aid
InoperativeOne or more main functions of the
Tele Aid system are malfunctioning.Have the Tele Aid system checked by
an authorized Mercedes-Benz Light
Truck Center.
Tele Aid
BatteryThe emergency power battery for the
Tele Aid system is malfunctioning. If the
vehicle battery is also malfunctioning or
drained, Tele Aid will not be operational.Have the Tele Aid system checked by
an authorized Mercedes-Benz Light
Truck Center.
tFunction
unavailableThis display appears if buttont
ors on the multifunction steering
wheel is pressed and the vehicle is not
equipped with a telephone.
W Top Up
Washer FluidThe fluid level has dropped to about 1/3 of
total reservoir capacity.Add washer fluid (page 346).

456 Practical hints
Unlocking/locking in an emergency
Locking the vehicle
If you cannot lock the vehicle with the
SmartKey or KEYLESS-GO*, lock the vehi-
cle carrying out the following steps.
Close the front passenger door, the
rear right door and the tailgate.
Open the driver’s door and the rear left
door.
Press the central locking switch on the
driver’s door (
page 126).
The locking knobs of the front passen-
ger door and the rear doors move
down.
If the vehicle battery is disconnected or
drained:
Press down the locking knobs of
the front passenger door and the
rear doors manually.
Exit the vehicle.
Close the driver’s door.
Enter the vehicle through the rear left
door.
Press down the locking knob of the
driver’s door.
Exit the vehicle.
Close the rear left door.
The vehicle is locked.
Unlocking and opening the tailgate
A minimum height clearance of 7.2 ft
(2.20 m) is required to open the tailgate.If the tailgate can no longer be unlocked
and opened using the Œbutton on the
SmartKey or the KEYLESS-GO* function,
use the emergency release lever to unlock
and open the tailgate.
The emergency release lever is located on
the inside of the tailgate.
1Emergency release lever
2CoverRemove cover2 from the trim on the
tailgate.
Push release lever1 all the way to the
left.
Lift the tailgate.
!To prevent inadvertent lockout, make sure
to have the SmartKey or SmartKey with
KEYLESS-GO* with you before proceeding with
the next step. The next step will lock the vehicle.
iThis procedure does not arm the anti-theft
alarm system, nor does it lock the fuel filler flap.

461 Practical hints
Replacing SmartKey batteries
Replacing SmartKey batteries
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 autho-
rized Mercedes-Benz Light Truck 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.Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key1 from the
SmartKey or SmartKey with
KEYLESS-GO* (
page 455).1Mechanical key
2Battery compartment
Insert mechanical key1 into opening.
Press mechanical key1 in direction of
arrow.
The battery compartment2 is
unlatched.
Pull battery compartment2 out of the
SmartKey housing.
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.
The required replacement batteries are available
at any Mercedes-Benz Light Truck Center.


462 Practical hints
Replacing SmartKey batteries
3Batteries
4Contact spring
Pull out batteries3.
Using a line-free cloth, insert new
batteries3 under contact springs4
with the positive terminal (+) side
facing up.
Return battery compartment2 into
housing until it locks into place.
Slide mechanical key1 back into the
SmartKey or SmartKey with
KEYLESS-GO*.
Check the operation of the SmartKey
or SmartKey with KEYLESS-GO*.


489 Practical hints
Battery
Battery
The battery is located under the front
passenger seat.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Light Truck
Center about steps you need to observe.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.
iMercedes-Benz recommends to have the
battery replaced at an authorized
Mercedes-Benz Light Truck Center.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills immediate-
ly with clear water. Contact a
physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.

490 Practical hints
Battery
!The battery is a valve-regulated lead acid
(VRLA) battery, also referred to as “fleece” bat-
tery. Such batteries do not require topping-up of
the electrolyte level. VRLA batteries therefore do
not have cell caps and the battery cover is
non-removable. Do not attempt to open the bat-
tery as otherwise the battery will be damaged.
Even though VRLA batteries do not require top-
ping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the bat-
tery condition must be checked periodically by
performing a battery conductance test. Refer to
Maintenance Booklet for battery condition test-
ing intervals.
As with any other battery, the battery may dis-
charge if the vehicle is not operated for an ex-
tended period of time. You can connect a battery
maintenance charge unit tested and approved
for use on your vehicle model or disconnect the
battery to prevent battery discharge. Contact an
authorized Mercedes-Benz Light Truck Center
for more information.!The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the
factory-equipped battery.
The battery, the battery ventilation hose
(
page 495) and the lateral plug (page 495)
must always be securely installed when the
vehicle is in operation.
Warning!G
Jump starting must only be done using the
jump-start contacts located in the engine
compartment (
page 497).
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(
page 489).
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.