2005 MERCEDES-BENZ SPRINTER Service Repair Manual

CHARGING SYSTEM
TABLE OF CONTENTS
page page
CHARGING SYSTEM
SPECIFICATIONS
TORQUE ± 2.7L DIESEL................17
SPECIAL TOOLS.......................17
GENERATOR
DESCRIPTION.........................18
OPERATION...........................18
REMOVAL.............................18
INSTALLATION.........................18GENERATOR DECOUPLER PULLEY
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - GENERATOR
DECOUPLER.........................19
REMOVAL.............................20
INSTALLATION.........................21
VOLTAGE REGULATOR
DESCRIPTION.........................23
CHARGING SYSTEM
SPECIFICATIONS
TORQUE ± 2.7L DIESEL
DESCRIPTION N-m Ft. Lbs. In. Lbs.
B+ Terminal Nut at Top of Generator 13 - 115
Generator Mounting Bolts/Nut 54 40 -
Rear Generator Support Bracket Bolts (to engine) 28 - 250
Generator Decoupler 110 81 -
SPECIAL TOOLS
GENERATOR DECOUPLER TOOL #8433
GENERATOR DECOUPLER TOOL #8823
VACHARGING SYSTEM 8F - 17

GENERATOR
DESCRIPTION
The generator is belt-driven by the engine using a
serpentine-type drive belt. It is serviced only as a
complete assembly. If the generator fails for any rea-
son, the entire assembly must be replaced.
On certain engines, the decoupler pulley may be
replaced separately.
OPERATION
As the energized rotor begins to rotate within the
generator, the spinning magnetic field induces a cur-
rent into the windings of the stator coil. Once the
generator begins producing sufficient current, it also
provides the current needed to energize the rotor.
The stator winding connections deliver the induced
AC current to 3 positive and 3 negative diodes for
rectification. From the diodes, rectified DC current is
delivered to the vehicle electrical system through the
generator battery terminal.
Although the generators appear the same exter-
nally, different generators with different output rat-
ings are used on this vehicle. Be certain that the
replacement generator has the same output rating
and part number as the original unit. Refer to Spec-
ifications and see Generator Ratings for amperage
ratings and part numbers.
Noise emitting from the generator may be caused
by: worn, loose or defective bearings; a loose or defec-
tive drive pulley (decoupler pulley); incorrect, worn,
damaged or misadjusted fan drive belt; loose mount-
ing bolts; a misaligned drive pulley or a defective sta-
tor or diode.
An instrument panel mounted, battery charge indi-
cator lamp is used. When the key is in the on posi-
tion, the lamp will be illuminated. This is done as a
bulb check. If this lamp remains illuminated while
the engine is running, a Diagnostic Trouble Code
(DTC) has been detected for the charging system.
REMOVAL
CAUTION: DISCONNECT NEGATIVE CABLE FROM
BATTERY BEFORE REMOVING BATTERY OUTPUT
WIRE FROM GENERATOR. FAILURE TO DO SO
CAN RESULT IN INJURY.
CAUTION: Never force a belt over a pulley rim
using a screwdriver. The synthetic fiber of the belt
can be damaged.
CAUTION: When installing a serpentine accessory
drive belt, the belt MUST be routed correctly. The
water pump will be rotating in the wrong direction ifthe belt is installed incorrectly, causing the engine
to overheat. Refer to belt routing label in engine
compartment, or refer to Belt Schematics in Cooling
System.
(1) Disconnect and isolate negative battery cable.
(2) Remove generator drive belt. Refer to Cooling
System for procedure.
(3) Raise and support vehicle.
(4) Remove protective plastic cover from B+ stud
at top of generator.
(5) Remove nut securing battery output cable to
B+ terminal at top of generator.
(6) Unplug field terminal connector at rear of gen-
erator.
(7) Remove 4 generator mounting bolts (Torx-style
#12 bit) (Fig. 1).
(8) Remove generator from lower side of vehicle.
INSTALLATION
(1) Raise and support vehicle.
(2) Position generator to engine.
(3) Install 4 generator mounting bolts (Fig. 1).
Refer to Torque Specifications.
Fig. 1 GENERATOR MOUNTING - 2.7L DIESEL
1 - GENERATOR
2 - DRIVE BELT
3 - MOUNTING BOLTS (4)
4 - GENERATOR WIRING HARNESS
8F - 18 CHARGING SYSTEMVA

(4) Connect field terminal connector at rear of gen-
erator.
(5) Install battery output cable and nut to B+ ter-
minal at top of generator. Refer to Torque Specifica-
tions.
(6) Install protective plastic cover to B+ stud at
top of generator.
(7) Lower vehicle.
CAUTION: Never force a belt over a pulley rim
using a screwdriver. The synthetic fiber of the belt
can be damaged.
CAUTION: When installing a serpentine accessory
drive belt, the belt MUST be routed correctly. The
water pump will be rotating in the wrong direction if
the belt is installed incorrectly, causing the engine
to overheat. Refer to belt routing label in engine
compartment, or refer to Belt Schematics in Cooling
System.
(8) Install generator drive belt. Refer to Cooling
System for procedure.
(9) Connect negative battery cable.
(10) Check charging system for proper operation.
GENERATOR DECOUPLER
PULLEY
DESCRIPTION
The generator decoupler is used only with
certain engines.The decoupler is used in place of
the standard generator drive pulley (Fig. 2).
OPERATION
The generator decoupler is used only with
certain engines.The decoupler (Fig. 2) is a one-way
clutch designed to help reduce belt tension fluctua-
tion, vibration, reduce fatigue loads, improve belt life,
reduce hubloads on components, and reduce noise.
Dry operation is used (no grease or lubricants). The
decoupler is not temperature sensitive and also has a
low sensitivity to electrical load. The decoupler is a
non-serviceable item and is to be replaced as an
assembly.
DIAGNOSIS AND TESTING - GENERATOR DECOUPLER
CONDITION POSSIBLE CAUSES CORRECTION
Does not drive generator
(generator not charging)Internal failure Replace decoupler
Noise coming from
decouplerInternal failure Replace decoupler
Fig. 2 GENERATOR DECOUPLER PULLEY
VACHARGING SYSTEM 8F - 19
GENERATOR (Continued)

REMOVAL
The generator decoupler is used only with
certain engines.
Two different type generator decoupler pulleys are
used. One can be identified by the use of machined
splines (Fig. 3). The other can be identified by a hex
opening (Fig. 4) and will not use splines.
Different special tools are required to service each
different decoupler. Refer to following procedure.INA Decoupler
(1) Disconnect negative battery cable.
(2) Remove generator and accessory drive belt.
Refer to Generator Removal.
(3) Position Special Tool #8823 (VM.1048) into
decoupler (Fig. 5).
(4) Determine if end of generator shaft is hex
shaped (Fig. 6) or is splined (Fig. 7). If hex is used,
Fig. 5 #8823 TOOL AND INA DECOUPLER
1 - INA DECOUPLER
2 - TOOL #8823 (VM.1048)
Fig. 6 END OF GENERATOR SHAFT (HEX)
1 - GENERATOR SHAFT
2 - HEX
Fig. 3 GENERATOR DECOUPLER PULLEY (INA)
1 - GENERATOR
2 - DECOUPLER (INA)
3 - MACHINED SPLINES
Fig. 4 GENERATOR DECOUPLER PULLEY (LITENS)
1 - DECOUPLER (LITENS)
2 - HEX OPENING
8F - 20 CHARGING SYSTEMVA
GENERATOR DECOUPLER PULLEY (Continued)

insert a 10MM deep socket into tool #8823 (VM.1048)
(Fig. 8). If splined, insert a 5/16º 6-point hex driver,
or a 10MM 12-point triple square driver into tool
#8823 (VM.1048) (Fig. 9).
(5) The generator shaft uses conventional right-
hand threads to attach decoupler. To break decoupler
loose from generator threads, rotate end of tool clock-
wise (Fig. 8) or, (Fig. 9).
(6) After breaking loose with tool, unthread decou-
pler by hand from generator.
Litens Decoupler
(1) Disconnect negative battery cable.
(2) Remove generator and accessory drive belt.
Refer to Generator Removal.
(3) Position Special Tool #8433 (Fig. 10) into
decoupler. Align to hex end of generator shaft.
(4) The generator shaft uses conventional right-
hand threads to attach decoupler. To break decoupler
loose from generator threads, rotate end of tool clock-
wise (Fig. 11).
(5) After breaking loose with tool, unthread decou-
pler by hand from generator.
INSTALLATION
INA Decoupler
(1) Thread decoupler pulley onto generator shaft
by hand (right-hand threads).
(2) Position Special Tool #8823 (VM.1048) into
decoupler (Fig. 5).
(3) Determine if end of generator shaft is hex
shaped (Fig. 6) or is splined (Fig. 7). If hex is used,
insert a 10MM deep socket into tool #8823 (VM.1048)
(Fig. 12). If splined, insert a 5/16º 6-point hex driver,
or a 10MM 12-point triple square driver into tool
#8823 (VM.1048) (Fig. 13).
Fig. 7 END OF GENERATOR SHAFT (SPLINED)
1 - GENERATOR SHAFT
2 - SPLINES
Fig. 8 DECOUPLER REMOVAL (INA-HEX)
1 - DEEP 10 MM SOCKET
2 - TOOL #8823 (VM.1048)
Fig. 9 DECOUPLER REMOVAL (INA-SPLINED)
1 - DRIVER
2 - TOOL #8823 (VM.1048)
3 - 17 MM WRENCH
VACHARGING SYSTEM 8F - 21
GENERATOR DECOUPLER PULLEY (Continued)

(4)Do not use an adjustable, ratcheting ªclick
typeº torque wrench. Most ªclick typeº
wrenches will only allow torque to be applied
in a clockwise rotation. Use a dial-type or
beam-type wrench.Tighten in counter-clockwise
rotation (Fig. 12) or, (Fig. 13). Refer to torque speci-
fications.
(5) Install accessory drive belt, and generator.
Refer to Generator Installation.
(6) Connect negative battery cable.Litens Decoupler
(1) Thread decoupler pulley onto generator shaft
by hand (right-hand threads).
Fig. 10 # 8433 TOOL AND LITENS DECOUPLER
Fig. 11 DECOUPLER REMOVAL (LITENS)
Fig. 12 DECOUPLER INSTALLATION (INA-HEX)
1 - 10MM DEEP SOCKET
2 - TOOL # 8823 (VM.1048)
Fig. 13 DECOUPLER INSTALLATION (INA SPLINED)
1 - DRIVER
2 - TOOL # 8823 (VM.1048)
8F - 22 CHARGING SYSTEMVA
GENERATOR DECOUPLER PULLEY (Continued)

(2) Position Special Tool 8433 (Fig. 10) into decou-
pler. Align tool to hex end of generator shaft.
(3)Do not use an adjustable, ratcheting ªclick
typeº torque wrench. Most ªclick typeº
wrenches will only allow torque to be applied
in a clockwise rotation. Use a dial-type or
beam-type wrench.Tighten in counter-clockwise
rotation (Fig. 14). Refer to torque specifications.
(4) Install accessory drive belt, and generator.
Refer to Generator Installation.
(5) Connect negative battery cable.VOLTAGE REGULATOR
DESCRIPTION
The electronic voltage regulator is attached to the
back of the generator. It is not serviced as a separate
component. If replacement is necessary, the generator
must be replaced.
Fig. 14 DECOUPLER INSTALLATION (Litens)
VACHARGING SYSTEM 8F - 23
GENERATOR DECOUPLER PULLEY (Continued)

STARTING SYSTEM
TABLE OF CONTENTS
page page
STARTING SYSTEM
DESCRIPTION.........................24
OPERATION...........................24
DIAGNOSIS AND TESTING - STARTING
SYSTEM............................25
SPECIFICATIONS
TORQUE - STARTER - DIESEL...........29
SPECIFICATIONS - STARTER MOTOR -
DIESEL.............................29STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER
MOTOR .............................29
REMOVAL.............................30
INSTALLATION.........................31
STARTER MOTOR RELAY
DESCRIPTION.........................31
REMOVAL.............................31
INSTALLATION.........................32
STARTING SYSTEM
DESCRIPTION
The starting system consists of:
²Starter relay
²Starter motor (including an integral starter sole-
noid)
Other components to be considered as part of start-
ing system are:
²Battery
²Battery cables
²Ignition switch and key lock cylinder
²Park/neutral position switch (automatic trans-
mission)
²Wire harnesses and connections.
The Battery, Starting, and Charging systems oper-
ate in conjunction with one another, and must be
tested as a complete system. For correct operation of
starting/charging systems, all components used in
these 3 systems must perform within specifications.
When attempting to diagnose any of these systems, it
is important that you keep their interdependency in
mind.
The diagnostic procedures used in each of these
groups include the most basic conventional diagnostic
methods, to the more sophisticated On-Board Diag-
nostics (OBD) built into the Engine Control Module
(ECM). Use of an induction-type milliampere amme-
ter, volt/ohmmeter, battery charger, carbon pile rheo-
stat (load tester), and 12-volt test lamp may be
required.
Certain starting system components are monitored
by the ECM and may produce a Diagnostic Trouble
Code (DTC).
OPERATION
The starting system components form two separate
circuits. A high-amperage feed circuit that feeds thestarter motor high-amperage, and a low-amperage
control circuit that operates on less than 20 amperes.
The high-amperage feed circuit components include
the battery, the battery cables, the contact disc por-
tion of the starter solenoid, and the starter motor
itself. The low-amperage control circuit components
include the ignition switch, the park/neutral position
switch (automatic transmission), the starter relay,
the electromagnetic windings of the starter solenoid,
and the connecting wire harness components.
If the vehicle is equipped with an automatic trans-
mission, battery voltage is supplied through the low-
amperage control circuit to the coil battery terminal
of the starter relay when the ignition switch is
turned to the momentary Start position. The park/
neutral position switch is installed in series between
the starter relay coil ground terminal and ground.
This normally open switch prevents the starter relay
from being energized and the starter motor from
operating unless the automatic transmission gear
selector is in the Neutral or Park positions.
When the starter relay coil is energized, the nor-
mally open relay contacts close. The relay contacts
connect the relay common feed terminal to the relay
normally open terminal. The closed relay contacts
energize the starter solenoid coil windings.
The energized solenoid pull-in coil pulls in the sole-
noid plunger. The solenoid plunger pulls the shift
lever in the starter motor. This engages the starter
overrunning clutch and pinion gear with the starter
ring gear on the manual transmission flywheel or on
the automatic transmission torque converter or
torque converter drive plate.
As the solenoid plunger reaches the end of its
travel, the solenoid contact disc completes the high-
amperage starter feed circuit and energizes the sole-
noid plunger hold-in coil. Current now flows between
the solenoid battery terminal and the starter motor,
energizing the starter.
8F - 24 STARTING SYSTEMVA