2004 MERCEDES-BENZ ML500 alternator

242 Practical hintsWhat to do if …
What to do if …Lamps in instrument clusterGeneral information:
If a bulb in the instrument cluster fails to
light up during the bulb self-check when turning the key in steering lock to
position2, have it checked and replaced if
necessary.Problem
Possible cause
Suggested solution
-
The yellow ABS warning lamp
comes on while driving.
ABS has detected a malfunction and has
switched off. The BAS, ESP, 4-ETS and EBP
are also switched off.
The brake system is still functioning normally
but without ABS available.

Continue driving with added caution.
Wheels may lock during hard braking
reducing steering capability.

Have the system checked at an autho-
rized Mercedes-Benz Light Truck Cen-
ter as soon as possible.
Failure to follow these instructions in-
creases the risk of an accident.
The charging voltage has fallen below
10 volts. The ABS has switched off.
When the voltage is above this value
again, the ABS is operational again.
If necessary, have the generator
(alternator) and the battery checked.

254 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
#
The red charge indicator lamp
comes on when the engine is
running.
The battery is no longer charging.
Possible causes:

alternator malfunctioning


broken poly-V-belt

Stop immediately and check the
poly-V-belt.
If it is broken

Do not continue to drive, before the
poly-V-belt is replaced.
Notify an authorized Mercedes-Benz
Light Truck Center.
2
The yellow brake indicator lamp
comes on during braking or after
starting the engine.
The brake pads are worn down.

Have the system checked at an autho-
rized Mercedes-Benz Light Truck
Center.
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service book-
let.

278 Practical hintsBattery
BatteryThe battery is located on the passenger
side of the engine compartment.
1Negative terminal
2Positive terminal
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 223).
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 termi-
nal clamps while the engine is running
or the key is in the steering lock. Other-
wise the alternator and other electronic
components could be severely dam-
aged.
Have the battery checked regularly by
an authorized Mercedes-Benz Light
Truck Center.
Refer to Service Booklet for mainte-
nance intervals or contact your autho-
rized Mercedes-Benz Light Truck
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 battery only to avoid the risk
of acid burns in the event of an accident.

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

297 Technical data
Electrical system
Electrical system
Model
ML 350
ML 500
Generator (alternator)
14 V / 120 A
14 V / 150 A
Starter motor
12 V / 1.7 kW
12 V / 1.7 kW
Battery
12 V / 100 Ah
12 V / 100 Ah
Spark plugs
Bosch F 8 DPP332
Bosch F 8 DPER
Bosch F 8 DPP332
Bosch F 8 DPER
Electrode gap
0.039 in (1.0 mm)
0.039 in (1.0 mm)
Tightening torque
15 – 22 lb-ft (20 – 30 Nm)
15 – 22 lb-ft (20 – 30 Nm)

314 Technical termsPoly-V-belt drive
Drives engine-components (alternator,
AC compressor, etc.) from the engine.
Power train
Collective term designating all compo-
nents used to generate and transmit
motive power to the drive axles, includ-
ing


engine


clutch / torque converter


transmission


transfer case


drive shaft


differential


axle shafts / axlesRemote Vehicle Diagnostics
Transmission of vehicle data and cur-
rent location to the Mercedes-Benz
Customer Assistance Center for sub-
scribers to Tele Aid service.
REST
(Residual engine heat utilization)
Feature that uses the engine heat
stored in the coolant to heat the vehi-
cle interior for a short time after the en-
gine has been turned off.
Restraint system
Seat belts, belt tensioner, airbags and
child seat restraint systems. As inde-
pendent systems, their protective func-
tions complement one another.RON
(R
esearch O
ctane N
umber)
The Research Octane Number for gaso-
line as determined by a standardized
method. It is an indication of a gaso-
line's ability to resist undesired detona-
tion (knocking). The average of both
the ->MON (Motor Octane Number)
and RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.
Shift lock
When the vehicle is parked, this lock
prevents the transmission selector le-
ver from being moved out of positionP
without key turned and brake pedal de-
pressed.
SRS
(S
upplemental R
estraint S
ystem)
Seat belts, emergency tensioning de-
vice and airbags. Though independent
systems, they are closely interfaced to
provide effective occupant protection.