2007 MERCEDES-BENZ GL320CDI engine

444 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
on while the vehicle is standing
still and the engine is running or
during driving.You and/or your front passenger have
forgotten to fasten your seat belts.Fasten your seat belts.
The seat belt telltale goes out.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out.
telltale flashes and you addition-
ally hear an intermittent warning
chime with increasing intensity.The vehicle’s speed once exceeded 15 mph
(25 km/h) and you and/or your front pas-
senger have forgotten to fasten your seat
belts.Fasten your seat belts.
The seat belt telltale goes out and the
warning chime stops sounding.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out and the
warning chime stops sounding.
iAfter 60 seconds with an unfastened seat
belt the warning chime stops sounding and the
seat belt telltale illuminates continuously. The seat belt telltale will only go out if both, the
driver and front passenger’s seat belt are
fastened, or the vehicle is standing still and a
front door is opened.

457 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
DISTRONICcurrently unavailable
See Operator’s ManualDistronic* is deactivated because

the Distronic* cover in the
radiator grille is dirty

the functionality is impaired by
heavy precipitation or fog
Clean the Distronic* cover in the radiator
grille (
page 430).
Restart the vehicle.
Distronic* becomes operational again without
the engine being restarted when

dirt on the radiator grille has fallen off while
driving (e.g. slush or snow)

the system recognizes full sensor
availability due to lessening rain or because
the road is drying, for example

the message in the multifunction display
disappears
You can then operate Distronic* as usual again.

461 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
PShift to PYou have started the engine or
switched on the ignition with
KEYLESS-GO* and opened the
driver’s door with the automatic
transmission not set to positionP.Set the automatic transmission to
positionP.
or
Close the driver’s door.
Shift to P or N
to start engineYou have attempted to start the
engine with the KEYLESS-GO*
start/stop button while the auto-
matic transmission was set to
positionR orD.Set the automatic transmission to
positionP orN.
Make sure the brake pedal is depressed
when attempting to start the engine
with the KEYLESS-GO* start/stop but-
ton.
Only shift to
Park when
vehicle is stationaryYou have tried to shift the auto-
matic transmission into positionP
using the gear selector lever
although the vehicle is still in mo-
tion.Stop the vehicle.
Apply the parking brake (page 68).

469 Practical hints
What to do if …
Symbol messages
Display symbolDisplay messagesPossible cause/consequencePossible solution
#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 68).
 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 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.

472 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
;(USA only)
3(Canada only)
Check
brake fluid levelThere is insufficient brake fluid
in the reservoir.Risk of accident! Stop the vehicle in a
safe location or as soon at is safe to do
so.
Apply the parking brake (page 68).
Notify an authorized Mercedes-Benz
Light Truck Center. Do not add brake
fluid! This will not solve the problem.
? (USA only)
± (Canada only)
Engine
ServiceThere may be a malfunction in
the

fuel injection system

ignition system

exhaust system

fuel system
Have the engine checked by an
authorized Mercedes-Benz Light Truck
Center.
Warning!G
Driving with the message Check brake
fluid level
displayed can result in an ac-
cident. Have your brake system checked im-
mediately. Do not add brake fluid before
checking the brake system. Overfilling the
brake fluid reservoir can result in spilling
brake fluid on hot engine parts and the
brake fluid catching fire. You could be seri-
ously burned.!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks.

473 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
Ï Coolant level
Stop car, switch engine offThe coolant is too hot.
Among other possible causes
(the cooling fan could be
malfunctioning), the poly-V-belt
could be broken.Stop the vehicle in safe location or as
soon as it safe to do so.
Apply the parking brake (page 68).
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
water pump which may result in damage
to the engine. Contact 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 Limit-
ed Warranty.
(Continued on next page)

474 Practical hints
What 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 symbolDisplay messagesPossible cause/consequencePossible solution
Observe the coolant temperature in the
multifunction display (
page 164).
If the temperature raises again:
Contact an authorized Mercedes-Benz
Light Truck Center immediately.
Warning!G
Driving when your engine is overheated 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 which can occur just by open-
ing the engine hood. Stay away from the en-
gine 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.

475 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
B Top up Coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 382).
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 could 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.