Page 250 of 356

248 Practical hintsWhat to do if …Lamps in instrument clusterGeneral information:
If a bulb in the instrument cluster fails to
come on during the bulb self-check when switching on ignition, have it checked and
replaced if necessary.Problem
Possible cause
Suggested solution
-
The yellow ABS malfunction
indicator lamp comes on while
driving.
ABS has detected a malfunction and has
switched off. The BAS, ESP, and 4-ETS 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.
Page 263 of 356
261 Practical hints
What 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 Maintenance
Booklet.
Page 290 of 356

288 Practical hintsBatteryThe battery is located on the passenger
side of the engine compartment.
1Negative terminal
2Positive terminal
Warning!
G
Failure to follow these instructions can
result in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 228).
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 Maintenance Booklet for main-
tenance intervals or contact an 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.
Page 307 of 356
305 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
Page 311 of 356
309 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)
Page 328 of 356

326 Technical termsParktronic (Parking assist)*
System which uses visual and acoustic
signals to assist the driver during park-
ing maneuvers.
Poly-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.