check engine MERCEDES-BENZ C300 4MATIC 2008 W204 Owner's Guide

363 Operation
Maintenance
Maintenance service term exceeded
If you have exceeded the suggested main-
tenance service term, you will see the fol-
lowing message in the multifunction
display:
Service A Exceeded by XXXX miles (km)
Service A Exceeded by XXX days
In addition, a signal sounds when the mes-
sage appears.
Any authorized Mercedes-Benz Center will
reset the maintenance service indicator
following a completed maintenance
service.
Calling up the maintenance service
indicator display
You can call up the maintenance service in-
dicator display at any time to check when
the next maintenance service is due.
Switch on the ignition.
The standard display of the control sys-
tem appears (
page 156).
Press ( or & on multifunction
steering wheel to select
Service menu.
Press % or $ to select the main-
tenance service indicator display.
Press #.
The service deadline appears in the
multifunction display.Resetting the maintenance service
indicator
In the event that the maintenance service
on your vehicle is not carried out at an
authorized Mercedes-Benz Center, you can
have the maintenance service indicator
reset. The automotive maintenance facility
carrying out the maintenance service will
find the information for resetting the
maintenance service indicator in the
maintenance-relevant information for your
vehicle. Such information is available from
either your authorized Mercedes-Benz
Center or directly from Mercedes-Benz.
iThe menu overview can be found on
(
page 154).
iIf the battery is disconnected, the days of
disconnection will not be included in the count
shown by the maintenance service indicator.
To arrive at the true maintenance service
deadline, you will need to subtract these days
from the days shown in the maintenance service
indicator message or maintenance service
indicator display.
iIf the maintenance service indicator was
inadvertently reset, have an authorized
Mercedes-Benz Center correct it.
Only reset if the proper maintenance service has
been performed. Resetting the system without
performing the proper service as called for by
the maintenance service indicator will result in
engine damage and/or other vehicle damage not
covered by the Mercedes-Benz Limited
Warranty.

374 Practical hints
What to do if …?
Lamps in instrument cluster
General information:
If any of the following lamps in the instru-
ment cluster fails to come on during the
bulb self-check when switching on the igni-
tion, have the respective bulb checked and
replaced if necessary.
ProblemPossible cause/consequenceSuggested solution
-The yellow Antilock
Brake System (ABS)
indicator lamp comes on
while the engine is
running.The ABS has detected a malfunction and
has switched off. The BAS, ESP® and EBP
are also switched off (see messages in mul-
tifunction display).
The brake system is still functioning nor-
mally but without the systems specified
above.
If the ABS control unit is malfunctioning,
other systems such as navigation system*
or the automatic transmission* may also be
malfunctioning.
Continue driving with added caution.
Wheels will lock during hard braking, re-
ducing steering capability.
Read and observe messages in the mul-
tifunction display (
page 387).
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
Failure to follow these instructions
increases the risk of an accident.

375 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
-The yellow Antilock
Brake System (ABS)
indicator lamp comes on
while the engine is
running.The charging voltage has fallen below
10 volts. The ABS has switched off. The
BAS, ESP
® and EBP are also switched off
(see messages in the multifunction display)
The battery may not be charged sufficiently.
Switch off electrical consumers that are
currently not needed, e.g. seat heat-
ing*.
If necessary, have the generator and
battery checked.
When the voltage is above this value again,
the ABS is operational again and the ABS in-
dicator lamp should go out.
-The yellow ABS indicator
lamp comes on while the
engine is running.The ABS is temporarily not available. The
ESP®, BAS and EBP are also unavailable.
The system’s self-diagnosis may not be
completed yet.
The brake system is still functioning nor-
mally but without the systems specified
above.
Drive a short distance with added
caution at a vehicle speed of above
12 mph (20 km/h).
When the ABS indicator lamp goes out,
the ABS, ESP
®, BAS and EBP are avail-
able again.
If the ABS indicator lamp does not go out:
Continue driving with added caution.
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
Failure to follow these instructions increas-
es the risk of an accident.

376 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
-
vThe yellow ABS malfunc-
tion indicator lamp and
the yellow ESP
® warning
lamp come on while the
engine is running and an
acoustic warning sounds.
ABS and ESP® are switched off due to a
malfunction.
The BAS and EBP are also switched off.
The brake system is still functioning nor-
mally but without the ABS available.Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the mul-
tifunction display (
page 387).
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
Failure to follow these instructions increas-
es the risk of an accident.
;
(USA only)
3
(Canada only)
-
v
The red brake warning
lamp comes on while the
engine is running. In addi-
tion, the yellow ABS mal-
function indicator lamp,
and the yellow ESP
®
warning lamp come on
and an acoustic warning
sounds.
A malfunction in the Electronic Brake Pro-
portioning (EBP) was detected. The ABS,
BAS and ESP
® are also switched off (see
messages in multifunction display).
The brake system continues to function
normally, but without electronic support.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the mul-
tifunction display (
page 387).
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
Failure to follow these instructions increas-
es the risk of an accident.

377 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
;
(USA only)
3
(Canada only)
The red brake warning
lamp comes on while the
engine is running and an
acoustic warning sounds.You are driving with the parking brake set.Release the parking brake
(
page 130).
The red brake warning
lamp comes on while the
engine is running.There is insufficient brake fluid in the reser-
voir.Risk of accident!
Carefully stop the vehicle in a safe loca-
tion or as soon as it is safe to do so.
Depress the parking brake
(
page 134).
Contact an authorized Mercedes-Benz
Center.
Do not add brake fluid! This will not
solve the problem.
Warning!G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on.
Do not add brake fluid before checking the
brake system.
Overfilling the brake fluid reservoir can re-
sult in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously 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.

378 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
±The yellow engine malfunc-
tion indicator lamp comes
on while driving.There is a malfunction in:

The fuel management system

The ignition system

The emission control system

Systems which affect emissions
Such malfunctions may result in excessive
emissions values and may switch the en-
gine to its limp-home (emergency opera-
tion) mode.
Have the vehicle checked as soon as
possible at an authorized
Mercedes-Benz Center.
An on-board diagnostic connector is
used by the service station to link the
vehicle to the shop diagnostics system.
It allows the accurate identification of
system malfunctions through the read-
out of diagnostic trouble codes. It is lo-
cated in the front left area of the
footwell next to the parking brake pedal.
iIn some states you may be required by law
to have the vehicle serviced as soon as the
engine malfunction indicator lamp comes on.
Check local requirements.

379 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
±The yellow engine malfunc-
tion indicator lamp comes
on while driving.A 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.
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked at an au-
thorized Mercedes-Benz Center.
vThe yellow ESP® warning
lamp comes on while the
engine is running.The ESP® has been switched off with the
ESP® switch or has been switched off due
to a malfunction.
Risk of accident!
When the ESP
® is switched off it will not
stabilize the vehicle if the system recogniz-
es that the vehicle starts to skid or that a
wheel is spinning.
The cruise control is deactivated and can-
not be switched on.
Switch the ESP® back on (page 64).
Exceptions: (
page 63).
If leaving the ESP® switched off, adapt
your speed and driving to the prevailing
road, weather and traffic conditions.
If the ESP
® cannot be switched on:
Continue driving with added caution.
Observer additional messages that may
appear in the multifunction display
(
page 389).
Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.

392 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Shift
to PYou have turned off the engine with the
KEYLESS-GO* start/stop button (Canada only) in
gear selector lever positionN and opened the driv-
er’s door.
or
You have attempted to switch off the engine with the
KEYLESS-GO* start/stop button (Canada only) while
the gear selector lever was in positionR orD.Place the gear selector lever in positionP.
Shift to P or N
To Start EngineYou have attempted to start the engine while the au-
tomatic transmission* was set to position R or D.Move the gear selector lever to position P or N
(
page 140).
Tire Press. Monitor
Inoperative
(USA only)
The TPMS is malfunctioning.Have the TPMS checked at an authorized
Mercedes-Benz Center.
Wheel Sensors Error
Tire Pressure Monitor
Inoperative
(USA only)
There are wheels without appropriate wheel sensors
mounted (e.g. winter tires).Have the TPMS checked at an authorized
Mercedes-Benz Center.
Have the wheel sensors installed at an autho-
rized Mercedes-Benz Center.
Tire Press. Monitor
Currently Unavailable
(USA only)
The TPMS is unable to monitor the tire pressure due
to a nearby radio interference source.As soon as the causes of the malfunction have
been removed, the TPMS automatically be-
comes active again after a few minutes driving.

400 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
;Check
Brake Fluid LevelThere is insufficient brake fluid in the reser-
voir.Risk of accident!
Carefully stop the vehicle in a safe location or
as soon as it is safe to do so.
Depress the parking brake (page 134).
Contact an authorized Mercedes-Benz Cen-
ter.
Do not add brake fluid! This will not solve the
problem.
(USA only)
3
(Canada only)
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 can be serious-
ly 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.

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)