charging ISUZU TF SERIES 2004 Repair Manual
Page 2557 of 4264
STARTING AND CHARGING SYSTEM  6D3-3 
 
   
Starter 
Removal 
1.  Remove the battery ground cable. 
2.  Remove harness connectors (1) and (2). 
 
 
 
 
3.  Remove bolts from starter. 
 
 
 
Installation 
1. Install starter assembly. 
2.  Install mounting bolts and tighten bolts to specified torque.
 Torque: 51 N
 m (5.2 kgf
 m)
 
3. Connect harness. 
4.  Reconnect the battery ground cable. 
  
Page 2558 of 4264
6D3-4  STARTING AND CHARGING SYSTEM 
 
 Disassembled View 
Legend
1 Bolt
2 Magnetic Switch
3 Gear Case
4 Piston
5 Piston Shaft
6 Center Bracket7 Armature
8 Yoke Assembly
9 Brush and Brush Holder
10 Washer
11 Rear Cover
12 Through Bolt
 
 
  
Page 2559 of 4264
STARTING AND CHARGING SYSTEM  6D3-5 
 
  
 
Inspection and Repair 
Repair or replace necessary parts if extreme wear or damage 
is found during inspection. 
Armature 
Check for continuity between commutator and segment. 
Replace commutator if there is no continuity (i.e., 
disconnected). 
 
 
  
  Check for continuity between commutator and shaft. 
Also, check for continuity between commutator and armature 
core, armature core and shaft. Replace commutator if there is 
continuity (i.e., internally grounded). 
 
 
  
  
Brush 
Measure the length of brush. 
Replace with a new one, if it is below the limit. 
Brush Holder 
Check for continuity between brush holder (+) (4) and base (-). 
Replace, if there is continuity (i.e., insulation is broken). 
 
 
  
  
Magnetic Switch 
Check for continuity of shunt coil between terminals S and M. 
Replace, if there is no continuity (i.e., coil is disconnected). 
 
 
  
  
Continuity of Series Coil 
Check for continuity between terminals S and M. 
Replace, if there is no continuity (i.e., coil is disconnected). 
  
Page 2560 of 4264
6D3-6  STARTING AND CHARGING SYSTEM 
 
  
 
 Continuity of Contacts 
With the plunger faced downward, push down the magnetic 
switch. In this state, check for continuity between terminals B 
and M. Replace, if there is no continuity (i.e., contacts are 
faulty). 
 
 
  
  
Pinion 
Check if the pinion rotates smoothly in drive direction by hand, 
or if it is locked when it is rotated in reverse. If not, replace the 
pinion. 
 
 
  
  
Characteristic Test 
For easily confirming the characteristics, conduct the noload 
test as follows: 
Rating as short as 30 seconds requires rapid testing. 
Fix the starter on the test bench, and wire as shown in 
illustration. When the switch is closed, the current flows and 
the starter runs under no load. At this time, measure current, 
voltage and speed to check if they satisfy the standard. 
Legend 
1 Volt Meter 
2 Revolution Indicator 
3 Battery 
4 Ammeter 
5 Switch 
  
Page 2561 of 4264
STARTING AND CHARGING SYSTEM  6D3-7 
  
Charging System 
General Description 
The charging system is an IC integral regulator charging 
system and its main components are connected as shown in 
illustration. 
The regulator is a solid state type and it is mounted along with 
the brush holder assembly inside the generator installed on the 
rear end cover. 
The generator does not require particular maintenance such as 
voltage adjustment. The rectifier connected to the stator coil 
has eight diodes to transform AC voltage into DC voltage. 
This DC voltage is connected to the output terminal of 
generator. 
 
Legend
1 Startor assembly
2 Housing
3 Slipring
4 Screws (2)
5 Regulator
6.Bolt (4)7 Rectifier assem bly
8 Retaining assem bly
9 B+ terminal nut and washer
10 Pulley
11 Rotor assembly
12 Ball bearing
2
11
12
28 54
31
11 7 6 10
9
 
  
Page 2562 of 4264
6D3-8  STARTING AND CHARGING SYSTEM 
 
 General On-Vehicle Inspection 
The operating condition of charging system is indicated by the 
charge warning lamp. The warning lamp comes on when the 
starter switch is turned to "ON" position. The charging system 
operates normally if the lamp goes off when the engine starts.
If the warning lamp shows abnormality or if undercharged or 
overcharged battery condition is suspected, perform diagnosis 
by checking the charging system as follows: 
1.  Check visually the belt and wiring connector. 
2. With the engine stopped, turn the stator switch to "ON"
position and observe the warning lamp. 
  If lamp does not come on: 
  Disconnect wiring connector from generator, and ground
the terminal "L" on connector side. 
  If lamp comes on: 
  Repair or replace the generator. 
 
  
 
 
 Generator 
Removal 
1.  Disconnect battery ground cable. 
2.  Move drive belt tensioner to loose side using wrench then
remove drive belt. 
3.  Disconnect terminal "B" wiring connector and connector. 
4.  Remove generator assembly. 
 
Generator Power and Circuit Diagram
 
 
 
Inspection 
Legend 
1 Load resistor, set parallel to battery 
2 Battery 
3 Voltmeter 
4 Ammeter 
5 Ignition Lock 
6 Charge Telltale 
7 Generator 
 
1. Disconnect battery. 
2.  Close off connecting cable from alternator terminal "B+". 
3.  Set ammeter (measuring range 100A) in disconnected line.
4.  Connect controllable load resistor to battery terminal. 
5.  Set resistor in front of connection to "O"; connect first to
battery, then to resistor. 
6. Connect tachometer. 
7. Connect oscilloscope according to manufacturer's
instructions. 
8. Connect battery. 
9.  Start engine and read off resulting current at various engine
speeds. 
  
Page 2563 of 4264
STARTING AND CHARGING SYSTEM  6D3-9 
 
  
 
 Generator Power 
1.  Adjust load resistor, if the required load currents are not 
attained. 
2. The shape of the voltage curves on oscilloscope curve
should be regular. 
3.  Test value: 5 to 7A. 
4.  If the required minimum current intensity is not attained, o
r
if the oscilloscope picture shows variations, the alternator
should be overhauled. 
 
Regulated Voltage Circuit Diagram
 
 
 Legend 
1 Battery 
2 Ignition Lock 
3 Charge Telltale 
4 Resistor, for attainment of load current with the battery set in 
series 
5 Voltmeter 
6 Ammeter 
7 Generator 
 
 
  
 
Installation 
1.  Install generator assembly and bring generator assembly to
the position to be installed. 
2. Install generator assembly and tighten to the specified
torque. 
 Torque: 
  Long bolt: 35 N
 m (3.6 kgf
 m) 
  Short bolt: 20 N
 m (2.0 kgf
 m) 
3.  Connect wiring harness connector. 
4.  Move drive belt tensioner to loose side using a wrench, then
install drive belt to normal position. 
5. Reconnect battery ground cable. 
  
Page 2564 of 4264
6D3-10  STARTING AND CHARGING SYSTEM 
  The generator has four external connections; the "B+" lead to 
battery positive, "L" lead to the warning lamp circuit(max. 2 
watts), "S" lead to battery positive terminal for battery sensing 
and an earth connection. 
 
  Explanation of type inscripiton 
Example:KC-A--> 14V 50-90A. 
 
K  = Code for Stator OD(126mm OD). 
C = Compact Generator. 
A  = Ausland (countries other than Germany) 
>  = Direction of rotation(clockwise). 
14V = Generator Operating Voltage. 
50A = Stabilised output at 25 C at 1800 RPM./13.5  
  Volts. 
90A = Stabilised output at 25 C at 1800 RPM./13.5  
  Volts. 
 
  Generator Connetions. 
B+  :  Battery Main Connection (battery positive) 
S  :  Battery Sense Connection(battery positive) 
L  :  Waring lamp(via warning lamp to Ignition switch) 
 
 
BATT.SENSE
REGULATOR ASSEMBLYHYBR10ALTERNATOR ASSEMBLY
12V BATT.1GN.SW.
300a* WARN.LAMP
1.2 WATT
L S8+SUPPRESSOR
CAPACITOR
0.5
f
NOTE: * RESISTOR IS RECOMMENDED TO
ENSURE THAT THE GENERATOR
REMAINS FUNCTIONAL IN CASE OF
WARNING LAMP FAILURE
  
Page 2565 of 4264
STARTING AND CHARGING SYSTEM  6D3-11 
 Warning  
Do not reverse S and L connections as this will destroy the 
warning lamp circuit of the regulator. 
Ensure good electrical contact beween generator  earth and 
battery negative, 
 
  Operation 
With the Iginiton switch turnded "ON", current is supplied via 
the warning lamp to the "L" terminal of the regulator. Base 
current is fed to T15 causing it to turn on, current then flows 
from B+ through the rotor winding via the regulator brushes 
and the collector emitter junction of T15 to earth completing 
the circuit.  The current in the rotor causes a magnetic field 
between adjacent poles to be created, this field is rotated and 
cuts the windings of the stator at right angles inducing a 
voltage into them. 
As the speed is increased this induced voltage increases and 
results in curent being rectified in the 3 phase diode bridge and 
supplied as DC to the B+ output and hence to the battery. 
When the voltage at the B+ terminal of the battery reaches 
around 14.2 volts, this voltage is monitored by the "S" lead and 
turns the regulator Hybrid base current to T15 OFF removing 
rotor current, resulting in a decrease in output voltage to below 
the regulating voltage, T15 base current turns ON and the 
whole cycle is repeated very rapidly. 
D38 protects T15 and the regulator against the back voltage 
developed across the rotor winding when T15 turns OFF. 
The new generated EP regulators incorporate current limiting 
in the warning lamp circuit. 
 
  Backup Regulation 
The EP regulator will limit the output voltage to a safe level 
should either the main B+ cable or the battery sense wire 
become decoupled, the output voltage will be slightly above the 
normal setting(1-3 volts). 
 
  Start up phase 
When the Iginition switch is turned on and the engine is not 
running, the current to the rotor is reduced by switching it on 
and off at a 50% duty cycle, the frequency is approximately 4 
KHz and may be audible at times. 
This is quite normal, once the engine is started normal 
regulation commences. 
 
 Warning lamp failure 
Should the warning lamp fail, the generator will self excite by 
deriving a small current from the phase connecion allowing the 
voltage to build up to regulating level.  
Note: no filed current will flow when the engine is cranking. 
  
Page 2566 of 4264
6D3-12  STARTING AND CHARGING SYSTEM 
  Diagnosis 
The EP regulator incorporates diagnostics which will illuminate 
the warning lamp as a result of fault conditions in the generator 
and external circuitry. 
 
These conditions include: 
1. 
An open circuit in the regulator battery sensing wire (S
Terninal) 
2.  An open circuit or excessive voltage drop in the B+ cable. 
3.  An open circuit in the generator phase connection. 
4.  Overcharging of the battery. 
5.  Regulator output stage short circuit. 
6. Open circuit rotor. 
 
The regulator compares the voltage at B+ with the voltage at 
the "S" terminal connceted to battery positive.  If the voltage 
differential exceeds a predetermined threshold, the regulator 
will operate in backup mode to limit the output voltage to a safe 
level.  The warning lamp; will remain illuminated as along as 
these conditions prevail. 
Sources of high resistance which will trigger the warning lamp 
are: 
 
a.  Poor contact in wiring harness connectors. 
b.  Poor contact between rectifier and regulator. 
c.  High resistance in fusible link assembly. 
 
 Caution: 
When bench testing the generator it is important that the 
warning lamp wattage of 2 watts is not exceeded.  
Reversal of the "S" and "L" on the regulator will damage 
the regulator. 
The correct plug for the regulator is a 9 122 067 011 for the 
Bosch tye and for the Shinagawa connector the number is 
X02FW. 
 
See appendix 1 for daignostic matrix. 
Before testing or disassembling the generator please observe 
the following points. 
 
1.  When testing the diodes with AC type testers the RMS.
Vlotage output must not exceed 12.0 volts, it is
recommended that the stator should be disconnected
during this test. 
2. Where zener power diodes are used, the breakdown
voltage should be tested to ensure all diodes have the
same zener voltage. 
3.  Insulation tests on the rotor and stator should use a voltage
not exceeding 110v for a series test lamp.  The rectifie
r
must be disconnected from the stator prior to testing. 
4.  When carrying out repairs to the charging system always
disconnected the battery negative first, and reconnect i
t
last.