2008 MERCEDES-BENZ ML550 key lock

391 Operation
Vehicle care
Do not apply any of these products or wax
if your vehicle is parked in the sun or if the
hood is still hot.
Use the appropriate MB-Touch-Up
Stick for quick and provisional repairs
of minor paint damage (i.e. chips from
stones, vehicle doors, etc.).
Engine cleaning
Prior to cleaning the engine compartment
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as
MB Anticorrosion Wax, should be applied
to the engine compartment after every en-
gine cleaning. Before applying, all control
linkage bushings and joints should be lu-
bricated. The poly-V-belt and all pulleys
should be protected from any wax.Vehicle washing
In the winter, thoroughly remove all traces
of road salt as soon as possible.
When washing the vehicle underbody, do
not forget to clean the inner sides of the
wheels.
Hand-wash
Do not use hot water or wash your vehicle
in direct sunlight.
Only use a mild car wash detergent,
such as Mercedes-Benz approved Car
Shampoo.
Thoroughly spray the vehicle with a dif-
fused jet of water.
Direct only a very weak spray towards
the ventilation intake.
Use plenty of water and rinse the
sponge and chamois frequently.
Rinse with clean water and thoroughly
dry with a chamois.
Do not allow cleaning agents to dry on
the finish.iVehicles with KEYLESS-GO*:
If a door handle is hit by a strong jet of water, and
a SmartKey with KEYLESS-GO* is in close
proximity, i.e. within approximately 3 ft (approxi-
mately 1 m), the vehicle could be inadvertently
locked or unlocked.
!Do not use scouring agents on these parts.
Never apply strong force and only use a soft,
non-sratching cloth when cleaning the vehicle.
Do not attempt to wipe the surface with a dry
cloth or sponge.
Otherwise you may scratch or damage the paint.

399 Practical hints
What to do if …
Where will I find ...?
Unlocking/locking in an emergency
Resetting activated head restraints
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Bleeding the fuel system
(diesel engine only)
Battery
Jump starting
Towing the vehicle
Fuses

429 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
;(USA only)
!(Canada only)
Release
Parking BrakeYou are driving with the parking
brake set.Release the parking brake (page 57).
;(USA only)
3(Canada only)
EBV, ABS, ESP Inoperative
See Operator’s ManualThe EBP, the ABS, and the ESP®
have switched off due to a mal-
function. The BAS is also
switched off.
The brake system is still func-
tional but without the EBP, the
ABS, and the ESP
® available.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Have the system checked at an
authorized Mercedes-Benz Light Truck
Center as soon as possible.
Failure to follow these instructions increases
the risk of an accident.

435 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
c You are driving with one or more
doors open.Stop the vehicle in a safe location or as
soon as it is safe to do so.
Close the door(s).
] Clean
Fuel FilterContact an authorized Mercedes-Benz
Light Truck Center.
AGas Cap OpenA loss of pressure has been
detected in the fuel system. The
fuel cap may not be closed
properly or the fuel system may
be leaky.Check the fuel cap (page 337).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an
authorized Mercedes-Benz Light Truck
Center.
aYou are driving with the hood or
the tailgate open.Carefully bring the vehicle to a halt as
soon as it is safe to do so in a safe
location.
Close the hood (page 341) or the
tailgate (
page 119).
You are trying to lock the vehicle
with the KEYLESS-GO* function
with a door or the tailgate open.Close all doors and/or the tailgate
(
page 119).

436 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
FKey
Not DetectedThe SmartKey with
KEYLESS-GO* is not detected
while the engine is running
because

the SmartKey with
KEYLESS-GO* is not in the
vehicle

there is strong
radio-frequency interference
Stop the vehicle in a safe location or as
soon as it is safe to do so.
Apply the parking brake (page 65).
Search for the SmartKey with
KEYLESS-GO*.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started
again after the engine is stopped.
The SmartKey with
KEYLESS-GO* is momentarily
not detected.Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.
Operate the vehicle with the SmartKey in
the starter switch if necessary.
Key
Not DetectedThe SmartKey with
KEYLESS-GO* is not detected
while the ignition is switched on
(
page 40) and a door is
opened or closed and the
SmartKey with KEYLESS-GO* is
not in the vehicle.
Search for the SmartKey with
KEYLESS-GO*.
Otherwise the vehicle cannot be locked
nor can the engine be started.
Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.

437 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
FKey Detected
In VehicleA SmartKey with KEYLESS-GO*
left in the vehicle was detected
while trying to lock the vehicle
from the outside.Take the SmartKey with KEYLESS-GO*
out of the vehicle.
Remove KeyYou have forgotten to remove
the SmartKey.Remove the SmartKey from the starter
switch.
You need a new key.There is no additional code avail-
able for SmartKey or SmartKey
with KEYLESS-GO*.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Key
Does Not Belong to VehicleThe SmartKey or SmartKey with
KEYLESS-GO* in the starter
switch does not belong to the
vehicle.Find the SmartKey or SmartKey with
KEYLESS-GO* that belongs to the
vehicle to operate the vehicle.
Change
Key BatteriesThe batteries in the SmartKey
with KEYLESS-GO* are dis-
charged.Replace the batteries (page 461).
Don’t Forget
Your KeyThis message appears for a
maximum of 60 seconds if the
driver’s door is opened with the
engine shut off and no SmartKey
in the starter switch.
This message is only a reminder.Insert the SmartKey in the starter
switch (
page 40).
or
Take the SmartKey with KEYLESS-GO*
with you when leaving the vehicle.

455 Practical hints
Unlocking/locking in an emergency
Unlocking/locking in an emergency
Unlocking the vehicle
If you cannot unlock the vehicle with the
SmartKey or KEYLESS-GO*, open the
driver’s door using the mechanical key.Removing the mechanical key
1Mechanical key locking tab
2Mechanical key
Move locking tab1 in direction of
arrow.
The mechanical key2 comes out.
Slide mechanical key2 out of the
housing.Unlocking the driver’s door
Insert mechanical key2 into the
driver’s door lock until it stops.
Turn mechanical key2 counterclock-
wise to position1 and hold it there.
Pull the door handle until the locking
knob moves up (
page 118).
The driver’s door is unlocked.
Pull the door handle once more to open
the driver’s door.
iUnlocking the driver’s door with the
mechanical key will trigger the anti-theft alarm
system.
To cancel the alarm, insert the SmartKey or
SmartKey with KEYLESS-GO* in the starter
switch.
1Unlocking
2Mechanical key

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.