2008 MERCEDES-BENZ C300 4MATIC instrument cluster

393 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front Passenger
Airbag Disabled
See Operator’s Manu-
alFront passenger front air bag is
deactivated while driving even
though an adult or someone
larger than a small individual is
occupying the front passenger
seat. Forces acting on the seat
may make the system sense a
decrease in weight.Stop the vehicle in a safe location as soon as possible and check the front
passenger seat for the following:
Switch off the ignition (page 82).
Have the front passenger vacate the seat and exit the vehicle.
Keep the seat unoccupied, close the front passenger door and switch
on the ignition (
page 82).
Monitor the
5/indicator lamp right of the instrument cluster
(
page 45) and the multifunction display in the instrument cluster
(
page 151) for the following:
(Continued on next page)

394 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front Passenger
Airbag Disabled
See Operator’s Manu-
alWith the seat unoccupied and the ignition switched on (page 82),

the 5/indicator lamp right of the instrument cluster should il-
luminate and remain illuminated, indicating that the OCS (
page 41)
has deactivated the air bag.

the message Front Passenger Airbag Enabled See Operator’s Man-
ual
or the message Front Passenger Airbag Disabled See Opera-
tor’s Manual
should not appear in the multifunction display at any time
the seat is unoccupied. Wait at least 60 seconds for the system to com-
plete the necessary check cycles and to make sure neither message ap-
pears in the multifunction display.
If above conditions are met, you can occupy the front passenger seat again.
Depending on the front passenger classification sensed by the OCS
(
page 41), the5/indicator lamp will remain illuminated or go
out.
If above conditions are not met, the system is not working properly. Have
the system checked as soon as possible at an authorized Mercedes-Benz
Center.
Warning!G
If the 5/indicator lamp remains
illuminated with an adult occupant on the
front passenger seat even after performing
the above corrective steps, do not have any
passenger use the front passenger seat until
the system has been repaired.

395 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front Passenger
Airbag Enabled
See Operator’s Manu-
alFront passenger front air bag is
activated while driving even
though a child, small individual,
or object below the system’s
weight threshold is on the front
passenger seat, or the front pas-
senger seat is empty. Objects
on the seat or forces acting on
the seat may make the system
sense supplemental weight.Stop the vehicle in a safe location as soon as possible and check the front
passenger seat for the following:
Switch off the ignition (page 82).
Remove child and child restraint from front passenger seat and properly
secure the child in rear seat employing the child restraint if necessary.
Make sure no objects which apply forces to the seat are present (e.g.
objects such as books, briefcases etc. lodged behind or around the
seat, head restraints pushing against roof, etc.). The system may recog-
nize such forces as supplemental weight and sense that an occupant on
the front passenger seat is of a greater weight than actually present.
Keep the seat unoccupied, close the front passenger door and switch
on the ignition (
page 82).
Monitor the
5/indicator lamp right of the instrument cluster
(
page 45) and the multifunction display in the instrument cluster
(
page 151) for the following:
(Continued on next page)

396 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front Passenger
Airbag Enabled
See Operator’s Manu-
alWith the seat unoccupied and the ignition switched on (page 82),

the 5/indicator lamp right of the instrument cluster should il-
luminate and remain illuminated, indicating that the OCS (
page 41)
has deactivated the air bag.

the message Front Passenger Airbag Enabled See Operator’s Man-
ual
or the message Front Passenger Airbag Disabled See Opera-
tor’s Manual
should not appear in the multifunction display at any time
the seat is unoccupied. Wait at least 60 seconds for the system to com-
plete the necessary check cycles and to make sure neither message ap-
pears in the multifunction display.
If above conditions are met, you can occupy the front passenger seat again.
Depending on the front passenger classification sensed by the OCS
(
page 41), the 5/indicator lamp will remain illuminated or go
out.
If above conditions are not met, the system is not working properly. Have
the system checked as soon as possible at an authorized Mercedes-Benz
Center.
Warning!G
If the 5/indicator lamp remains
illuminated with an adult occupant on the
front passenger seat even after performing
the above corrective steps, do not have any
passenger use the front passenger seat until
the system has been repaired.

402 Practical hints
What to do if …?
During severe operating conditions,
e.g. stop-and-go traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display Possible cause/consequencePossible solution
•Coolant Low
Stop Vehicle!
Turn Engine OffThe coolant is too hot. Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.
Only start the engine again after the message
disappears. You could otherwise damage the
engine.
Observe the coolant temperature gauge in
the instrument cluster (
page 26).
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 opening the engine hood. Stay
away from the engine if you see or hear
steam coming from it.
Stop the vehicle in a safe location away from
other traffic. 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). Do-
ing so may cause serious engine damage which
is not covered by the Mercedes-Benz Limited
Warranty.

403 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
•Coolant Low
Stop Vehicle!
Turn Engine OffThe poly-V-belt could be broken.Stop the vehicle in a safe location or as soon
a s it is sa fe t o do so and im media tely turn off
the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise the en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine.
Notify an authorized Mercedes-Benz 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 gauge in
the instrument cluster (
page 26).
(Continued on next page)

404 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
•Coolant Low
Stop Vehicle!
Turn Engine OffRestart the engine.
If this message disappears from the multi-
function display:
Drive immediately to the nearest autho-
rized Mercedes-Benz Center.
If this message does not disappear from the
multifunction display:
Call Roadside Assistance.
•The cooling fan for the coolant is malfunc-
tioning.Observe the coolant temperature gauge in
the instrument cluster (
page 26).
Have the fan replaced as soon as possible.

409 Practical hints
What to do if …?
ITake Your Key
From IgnitionYou have forgotten to remove the
SmartKey.Remove the SmartKey from the starter
switch.
.AUTO Lamp Function
InoperativeThe light sensor is malfunctioning. Daytime
driving lamps are switched on.In the instrument cluster control system, set
lamp operation to manual mode.
Switch on headlamps using the exterior lamp
switch.
Contact an authorized Mercedes-Benz Cen-
ter as soon as possible.
Check
Center Brake LampThe high mounted brake lamp is malfunc-
tioning. This message will only appear if all
light emitting diodes have stopped working.Contact an authorized Mercedes-Benz Cen-
ter as soon as possible.
Check
Left Brake LampThe left brake lamp is malfunctioning.Replace the bulb as soon as possible
(
page 436).
Check
Right Brake LampThe right brake lamp is malfunctioning.Replace the bulb as soon as possible
(
page 436).
Display Possible cause/consequencePossible solution