alternator MERCEDES-BENZ C300 4MATIC 2008 W204 Owner's Manual

389 Practical hints
What to do if …?
Text messages
Display Possible cause/consequencePossible solution
ABS and ESP
Currently Unavailable
See Operator’s ManualABS and ESP® are not available due to a malfunction.
BAS and the hill start assist are also switched off. It
is possible that the self-diagnostics have not yet
been completed.
The brake system still functions normally.Drive a short distance with gentle turns above a
speed of 12 mph (20 km/h).
The message disappears when ABS and ESP
®
are again available.
The ABS and ESP® were deactivated because of in-
sufficient power supply. The charging voltage has
fallen below 10 volts. BAS and the hill start assist are
also deactivated.
The brake system still functions normally but without
the ABS and ESP
® available.
When the voltage is above this value again, the ABS
and ESP® are operational again and the message in
the multifunction display should disappear.
If the message in the multifunction display does not
disappear:
Have the generator (alternator) and the battery
checked.
ABS and ESP
Inoperative
See Operator’s ManualABS and ESP® are switched off due to a malfunction.
BAS and the hill start assist are also switched off.
The brake system still functions normally but without
the ABS and 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 Center as soon as possible.
Failure to follow these instructions increases the
risk of an accident.

397 Practical hints
What to do if …?
Symbol messages
Display Possible cause/consequencePossible solution
-ABS and ESP
Currently Unavailable
See Operator’s ManualABS and ESP® are not available due to a
malfunction. BAS and the hill start assist
are also switched off. It is possible that the
self-diagnostics have not yet been complet-
ed.
The brake system still functions normally.Drive a short distance with gentle turns
above a speed of 12 mph (20 km/h).
The message disappears when ABS and
ESP
® are again available.
The ABS and ESP® were deactivated be-
cause of insufficient power supply. The
charging voltage has fallen below 10 volts.
BAS and the hill start assist are also deacti-
vated.
The brake system still functions normally
but without the ABS and ESP
® available.
When the voltage is above this value again,
the ABS and ESP® are operational again and
the message in the multifunction display
should disappear.
If the message in the multifunction display
does not disappear:
Have the generator (alternator) and the
battery checked.

399 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
#The battery is no longer charging.
Possible causes:

alternator malfunctioning

broken poly-V-belt
Stop the vehicle immediately in a safe loca-
tion and 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:
Drive immediately to the nearest authorized
Mercedes-Benz Center.
There is a malfunction in the electronic sys-
tem.Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
2Check
Brake Pad WearThe brake pads have reached their wear
limit.Have the brake pads replaced as soon as
possible.
!Brake pad thickness must be visually
checked by a qualified technician at the intervals
specified in the Maintenance Booklet.

447 Practical hints
Battery
1Filter box
2Clamps
Removing filter box: Release
clamps2.
Remove filter box.
Installing filter box: Insert filter box
properly.
Secure it with clamps2.
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and
precautions when handling automotive
batteries (
page 446).
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
!Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly at an autho-
rized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact an authorized
Mercedes-Benz Center for further information.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof batteries only to avoid the
risk of acid burns in the event of an
accident.
!Do not connect any consumers directly to
the battery or it will be discharged.

464 Technical data
Layout of poly-V-belt drive
C 300/C 350
1Idler pulley
2Idler pulley
3Automatic belt tensioner
4Power steering pump
5Air conditioning compressor
6Crankshaft
7Coolant pump
8Generator (alternator)

473 Technical data
Electrical system
Electrical system
ModelC 2301
C 230 Sport1
C 230 4MATIC1
C 230 4MATIC Sport1
1Canada only.
C 300
C 300 Sport
C 300 4MATIC
C 300 4MATIC SportC 3501
C 350 Sport
C 350 4MATIC1
C 350 4MATIC Sport1
Generator (alternator)14 V/150 A14 V/150 A14 V/150 A
Starter motor12 V/1.4 kW12 V/1.4 kW12 V/1.4 kW
Battery12 V/84 Ah12 V/84 Ah12 V/84 Ah
Spark plugsNGK PLKR 6A
Bosch Platin Y 7 MPP 33NGK PLKR 6A
Bosch Platin Y 7 MPP 33NGK PLKR 6A
Bosch Platin Y 7 MPP 33
Electrode gap0.031 in (0.8 mm)0.031 in (0.8 mm)0.031 in (0.8 mm)
Tightening torque15 – 22 lb-ft (20 – 30 Nm)15 – 22 lb-ft (20 – 30 Nm)15 – 22 lb-ft (20 – 30 Nm)