2004 ISUZU TF SERIES Voltage regulator

6E-350 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9
1. Using the Tech 2, ignition "On" and engine "Off".
2. Monitor the "Throttle Position" in the data display.
Does the Tech 2 indicate correct "Throttle Position"
from 0% to 100% depending on accelerator pedal
operation?
- Go to Step 11 Go to Step 10
10
1. Using the Tech 2, ignition "On" and engine "Off".
2. Monitor the "Throttle Position" in the data display.
3. Adjust the accelerator cable or TPS within 0% to
100%.
Is the action complete?
- Verify repair -
11
Check for the following conditions.

Objects blocking the throttle valve.

Vacuum leaking at throttle body.
If a problem is found, repair as necessary.
Was the problem found? - Verify repair Go to Step 12
12
Visually/physically inspect for the following conditions:

Restrict air intake system. Check for a restricted air
filter element, or foreign objects blocking the air
intake system.

Check for objects blocking the IAC passage or
throttle bore, excessive deposits in the throttle bore
and on the throttle plate.

Check for a condition that causes a large vacuum
leak, such as an incorrectly installed or faulty
crankcase ventilation hose/brake booster hose.
Was a problem found?
- Verify repair Go to Step 13
13
Perform the Injector Coil/Balance Test.
Refer to 6E-106 page
Was a problem found.
- Verify repair Go to Step 14
14
1. Check for fuel in the pressure regulator vacuum
hose.
2. If fuel is present, replace the fuel pressure regulator
assembly.
Was a problem found?
- Verify repair Go to Step 15
15
Check for proper ignition voltage output with the spark
tester.
Was a problem found?
- Verify repair Go to Step 16
16
1. Remove the spark plugs and check for gas or oil
fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must
be determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 17

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

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

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.

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.

STARTING AND CHARGING SYSTEM 6D3-13

5. During current output tests please make sure that the
ammeter is securely connceted into the charge circuit.
6. Some battery powered timing lights can produce high
transient voltages when connected or disconnected. Onl
y
disconnect or connect timing lights when the engine is
switched off.
7. Make sure the warning lamp circuit is functioning normall
y
before commencing tests.
8. Battery isolation switches must only be operated when the
engine is stopped.
9. To protect the charging system when using 240 vol
t
chargers it is recommeneded that the battery is
disconnected whilst charging.
10. Due to the very low resistance value of the stator winding i
t
may not be possible to obtain accurate readings withou
t
special equipment.
11. 12 volts must never be connected to the "L" terminal of the
regulator as this will damage the lamp driver circuit.
12. No loads apart from the warning lamp can be connected to
the "L" termainal. The "W" terminal is provided for this
purpose.

Disassembly
1. Mark the relative positions of the end housings in relation to
the stator assembly to aid reassembly. Use a permanen
t
marking pen do not use centre punched as this can cause
misalignmnet of the housings.
2. Remove the EP regulator from the slipring end housing b
y
removing the two screws. Tilt the regulator slightly from the
plug connection until the regulator clears the housing, then
lift clear.
3. Remove the four through bolts.
4. Carefully remove the stator assembly along with the slipring
end housing taking care not to put strain on the stator wires.
5. To disconnect the stator from the rectifier assembly, grasp
the stator wires close to the wire loop with a pair of long
nosed pliers, heat the joint with a soldering iron, when the
point becomes plastic apply a slight twisting motion to the
wires, then pull upwards to release the wires. Remove the
stator.
This procedure opens the wire loop to release the stato
r
connections easily.
6. To remove the rectifier remove the three retaining scre
w
and the B+ terminal nut and washers.

Note: the B+ bolt and the positive heatsink retaining screw are
fitted with mica insulating washers.
These must be discarded and replaced with new washers and
heatsink compound.

STARTING AND CHARGING SYSTEM 6D3-17
fan.

4. Replacing the brushes (inbuilt regulator)
Check the brushes for length, this is measured from the brush
holder to the end of the brush along it's centre line. Also
inspect for any sideways wear. If worn replace both brushes.
The minimum length is 3.8mm. Inspect the brush springs for
signs of corrosion or loss of tension or uneven tension.

Replacing the brushes, using a soldering iron apply heat to the
soldered joints on the rear of the brush holder of the regulator,
using a small lever prise up the retaining tabs to release the
brush lead and spring. Thread the new brush lead up the
brush holder along with the spring, pull the lead through the
tabs until the brush is protruding 12mm from the holder.
Bend down the tabs and solder the brush lead taking care not
to allow the solder to run up the lead which will reduce
flexibility. Use 60/40 resin cored solder.

5. Ball bearing
Please note the bearings used in this KCA generator are a
high
tolerance type, only fully sealed bearings of the same
specification are to be used as replacements. It is
recommended that the bearings be replaced during the
reconditioning process to restore the unit to original
specification.








6. Regulator
The regulator can only be tested when fitted into an altenator.

Warning: do not reverse"S" and "L" connections or put 12
volt supply to "L" terminal, this connection must not be
used as a supply source other than to supply the
requirements of the warning lamp 2(watts).
Such action will destroy the regulator warning lamp
circuit.

For test voltages refer to Generator output testing section.
See also additional information on regulator function earlier in
this instruction.

6D3-20 STARTING AND CHARGING SYSTEM
Load regulation test
Increase the engine speed until the generator is running at
6000 rpm, increase the load to 90% of full output a decrease in
the regulating voltage should not exceed 0.50 volts for 12 v
and 0.70 v for 24 v regulators of the readings obtained in the
previous test. If so, the regulator is defective.

Generator output test at full load
Increase engine speed until the altenator is running at 6000
rpm, switch on electrical loads until the generator voltage
drops to 13.5 volts for 12 v systems and 26 volts for 24 v
systems, full outut should be obtained under these conditions.
It may be necessary to adjust engine speed to maintain
altenator speed. If sufficient electrical loads are not available a
carbon pile resistance can be connected across the battery
and adjusted until maximum output is obtained.

Keep the time for this test to a minimum to avoid undue
heating and high engine speeds.