2006 MERCEDES-BENZ R350 engine

433 Practical hints
What to do if …
Display symbol
Display messages
Possible cause/consequence
Possible solution
?
(USA only)
±
(Canada only)
Engine Service
There may be a malfunction in
the

fuel injection system


ignition system


exhaust system


fuel system

Have the engine checked by an autho-
rized Mercedes-Benz Light Truck Center.
B
Coolant
Check level
The coolant level is too low.

Add coolant (
page 351).

If you have to add coolant frequently,
have the cooling system checked by an
authorized Mercedes-Benz Light Truck
Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat causing major
engine damage.

434 Practical hintsWhat to do if …
During severe operation conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbol
Display messages
Possible cause/consequence
Possible solution
Ï
Coolant
Stop, engine off
The coolant is too hot.

Stop the vehicle in a safe location or as
soon as it is safe to do so and immediate-
ly turn off the engine.

Only start the engine again after the
message disappears. You could
otherwise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
!The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious
damage which is not covered by the
Mercedes-Benz Limited Warranty.

435 Practical hints
What to do if …
Display symbol
Display messages
Possible cause/consequence
Possible solution
Ï
Coolant
Stop, engine off
The poly-V-belt could be broken.

Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.

Check the poly-V-belt.
If it is broken:

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

Do not continue to drive the vehicle with this
message displayed. Doing so could result in
serious engine damage that is not covered by
the Mercedes-Benz Limited Warranty.

Observe the coolant temperature in the
multifunction display (
page 168).

Drive immediately to the nearest authorized
Mercedes-Benz Light Truck Center.

437 Practical hints
What to do if …
Display symbol
Display messages
Possible cause/consequence
Possible solution
N
Check eng. oil level
when next refueling
The engine oil level is too low.

Check the engine oil level (
page 346).
USA only:Add 1 qt. engine oil
when next refuelingCanada only:Add 1 liter engine oil
when next refueling
The engine oil level is too low.

Add engine oil (
page 349) and check
the engine oil level (page 346).
Engine oil level
Stop, engine off
There is no oil in the engine.
There is a danger of engine
damage.

Carefully bring the vehicle to a halt as
soon as as it is safe to do so in a safe
location.

Turn off the engine.

Add engine oil (
page 349) and check
the engine oil level (page 346).
Engine oil level
Reduce oil level
You have added too much
engine oil. There is a risk of dam-
aging the engine or the catalytic
converter.

Have oil siphoned or drained off.
Observe all legal requirements with
respect to its disposal.
Change engine oil
Visit workshop
It may be that there is water in
the engine oil.

Have the engine oil checked.

438 Practical hintsWhat to do if …When the message
Add 1 qt. engine oil
when next refueling
(Canada:
1 liter
)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the mini-
mum level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest
service station where the engine oil should
be topped to the required level with an ap-
proved oil specified in the Factory
Approved Service Products pamphlet.
Display symbol
Display messages
Possible cause/consequence
Possible solution
N
Engine oil level
Visit workshop
The engine oil has dropped to a
critical level.

Check the engine oil level (
page 346)
and add oil as required (
page 349).

If you must add engine oil frequently, have
the engine checked for possible leaks.
Oil sensor malfunction
Visit workshop
The measuring system is
malfunctioning.

Have the measuring system checked by
an authorized Mercedes-Benz Light Truck
Center.
!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.

440 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause/consequence
Possible solution
F
Key
not recognized
The SmartKey with
KEYLESS-GO* is not recognized
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 as soon as it is safe to do
so.

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 recognized.

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 recognized
The SmartKey with
KEYLESS-GO* is not recognized
while the ignition is switched on
(page 38) 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.

441 Practical hints
What to do if …
Display symbol
Display messages
Possible cause/consequence
Possible solution
F
Key
still in vehicle
A SmartKey with KEYLESS-GO*
left in the vehicle was recog-
nized while trying to lock the ve-
hicle from the outside.

Take the SmartKey with KEYLESS-GO*
out of the vehicle.
Remove key
You have forgotten to remove
the SmartKey.

Remove the SmartKey from the starter
switch.
Replace key
Drive to workshop
There is no additional code avail-
able for SmartKey or SmartKey
with KEYLESS-GO*.

Visit an authorized Mercedes-Benz Light
Truck Center as soon as possible.
Key
Check battery
The batteries in the SmartKey
with KEYLESS-GO* are dis-
charged.

Replace the batteries (
page 464).
Do not
forget key
This 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 SmartKey in the starter switch.
or

Take the SmartKey with KEYLESS-GO*
with you when leaving the vehicle.

462 Practical hintsOpening / closing in an emergencyPower tilt/sliding sunroof*
You can open or close the tilt/sliding
sunroof manually should an electrical
malfunction occur.
The tilt/sliding sunroof drive is located
behind a cover on the overhead control
panel.
1Cover
Remove the SmartKey from the starter
switch.Vehicles with KEYLESS-GO*:

Turn off the engine by pressing the
KEYLESS-GO start/stop button
(page 66).

Open the driver’s door (this puts
the starter switch to position0,
same as with the SmartKey re-
moved from starter switch). The
driver’s door can then be closed
again.

Press on cover1 at the position indi-
cated by the arrow.

Take off cover 1.
2Crank

Take crank 2 out of the Operator’s
Manual pouch.

Insert crank2 into hole.

Turn crank2 clockwise to

slide sunroof closed


raise sunroof at the rear

Turn crank2 counterclockwise to

slide sunroof open


lower sunroof at the rear
iTurn crank2 slowly and smoothly.
The tilt/sliding sunroof must be syn-
chronized if it has been operated man-
ually (
page 258).
iThe panorama roof with power
tilt/sliding panel* cannot be operated
as described. Contact an authorized
Mercedes-Benz Light Truck Center.