2004 ISUZU TF SERIES Voltage regulator

6 – 16 TROUBLESHOOTING
14. Battery Charging and Noise Problem
Visual/physical check the following items before diagnosis.
The drive belt tension.
The battery terminals connection condition.
The ground connection condition.
The generator and the battery fastener condition.
The battery fluid level and specific gravity.
14-1 Battery No Charging
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed.
—
Go to Step 2 Go to
visual/physical
check
2 Inspect the brush contact condition on the generator.
Was there poor contact between the brush and the
slip ring? — Repair or
replace the
brush and/or
the slip ring. Go to Step 3
3 Inspect the stator coil on the generator.
Was there an open circuit or the scorching on the
stator coil? —
Replace the
stator coil. Go to Step 4
4 Inspect the rotor coil on the generator.
Was there an open circuit or the scorching on the
rotor coil? —
Replace the
rotor coil. Go to Step 5
5 Inspect the rectifier on the generator.
Was the rectifier defective? — Replace the
rectifier Go to Step 6
6 Inspect the IC regulator.
Was the IC regulator defective? — Replace the IC
regulator. Go to Step 7
7 Are any DTC stored? — Go to indicated
DTC. Solved

14-2 Battery Overcharging
Step Action Value(s) Yes No
1 Was “Visual/Physical Check" performed.
—
Go to Step 2 Go to
visual/physical
check
2 Inspect the terminal circuit.
Were the B and F terminals shorted? — Repair the
short circuit. Go to Step 3
3 Check the regulating voltage.
Was the IC regulator voltage excessive? — Replace the IC
regulator. Go to Step 4
4 Are any DTC stored? — Go to indicated
DTC. Solved

6D – 2 ENGINE ELECTRICAL

MAIN DATA AND SPECIFICATIONS
Description
Item
60A 80A
Generator
Type
AC generator with IC regulator and vacuum pump
Hitachi LR160-503E Hitachi LR180-513B
Voltage V
Drive and rotation
Ground polarity 12
V-belt, clockwise viewed from the drive pulley
Negative
Maximum output A 60 80
Engine speed ratio to 1 1.788
Maximum speed rpm 11,000
Weight with vacuum pump kg(lb) 5.8(12.8) 6.4(14.1)
Vacuum Pump
Delivery volume cm3/rev
Exhaust Characteristic


Maximum vacuum
50
-66.7 kPa (-500 mmHg) bulid up time 21 seconds or less at 1,000
rpm

7 seconds or less at 5,000 rpm
-90.7 kPa (-680 mmHg) or more
Starter Motor
Type
Solenoid controlled
Hitachi S13-555
12
2.3

8.76
300 Rated voltage V
Rated output kW
Load characteristics
Terminal voltage V
Load current A
Weight kg(Ib)
4.7 (10.4)

ENGINE ELECTRICAL 6D – 3

GENERAL DESCRIPTION
GENERATOR STARTER MOTOR



066L300004065L300002

The basic charging system is the IC integral regulator charging system. The internal components are connected
electrically as shown in charging circuit diagram.
The generator features a solid state regulator that is mounted inside the generator. All regulator components are
enclosed into a solid mold, and this unit along with the brush holder assembly is attached to the slip ring end frame.
The generator voltage setting cannot be adjusted.
The starter motor circuit is composed of a 4-pole 4-brush type direct current series motor. The starter motor circuit
utilizes negative ground polarity.

6D – 14 ENGINE ELECTRICAL
RECTIFIER ASSEMBLY



RTW46DSF000301

1. Voltmeter
2. Switch 1
3. DC regulated power supply
4. Lamp 2
5. Lamp 1
6. Switch 3
7. Switch 2
8. Pulse generator
9. Output signal

Test circuit
Refer to the judgment criteria shown in the Table below.
Carefully check Items 1~5. If all the items are OK, the IC
regulator is normal.

Circuit components
1 DC regulated power supply 0~20 volts variable with output of 1 ampere or more
2 Lamps (2) 12 volts, 1.4~3.4 watts
3 Switches (3) -----
4 DC voltmeter 0~30 volts, 0.5 grade
5 Pulse generator (Oscillator) 5~30 volt output at a frequency of 1kHz

Judgment criteria
Lamp condition
No. Switch
1 Switch
2 Switch
3 Voltmeter
reading
Lamp 1 Lamp 2Remarks
1 ON OFF OFF On
(dim) ON Initial excitation check
2 ON ON OFF 12V
On or
flashingFull excitation check
3 ON ON OFF 16V Off or
on (dim)OFF
Lamp 1 off or dimly lit when the
voltmeter shows less than 12 volts or
16 volts
4 OFF ON OFF 12V On or
flashingStator and brush separation check
5 ON ON ON 18V On ON
Excess voltage check

STARTING AND CHARGING SYSTEM (6VE1 3.5L) 6D3-15
Charging System
General Description
The 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 eigh
t
diodes to transform AC voltage into DC voltage.
This DC voltage is connected to the output terminal o
f
generator.

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 i
f
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.




F06RW009

6E-56 3.5L ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR FUEL
METERING
The fuel metering system starts with the fuel in the fuel
tank. An electric fuel pump, located in the fuel tank,
pumps fuel to the fuel rail through an in-line fuel filter.
The pump is designed to provide fuel at a pressure
above the pressure needed by the injectors.
A fuel pressure regulator in the fuel rail keeps fuel
available to the fuel injectors at a constant pressure.
A return line delivers unused fuel back to the fuel tank.

The basic function of the air/fuel metering system is to
control the air/fuel delivery to the engine. Fuel is
delivered to the engine by individual fuel injectors
mounted in the intake manifold.
The main control sensor is the heated oxygen senso
r
located in the exhaust system. The heated oxygen
sensor reports to the ECM how much oxygen is in the
exhaust gas. The ECM changes the air/fuel ratio to the
engine by controlling the amount of time that fuel
injector is "On".
The best mixture to minimize exhaust emissions is 14.7
parts of air to 1 part of gasoline by weight, which allows
the catalytic converter to operate most efficiently.
Because of the constant measuring and adjusting of the
air/fuel ratio, the fuel injection system is called a "closed
loop" system.
The ECM monitors signals from several sensors in
order to determine the fuel needs of the engine. Fuel is
delivered under one of several conditions called
"mode". All modes are controlled by the ECM.

Acceleration Mode
The ECM provides extra fuel when it detects a rapid
increase in the throttle position and the air flow.

Battery Voltage Correction Mode
When battery voltage is low, the ECM will compensate
for the weak spark by increasing the following:

The amount of fuel delivered.

The idle RPM.

Ignition dwell time.

Clear Flood Mode
Clear a flooded engine by pushing the accelerator pedal
down all the way. The ECM then de-energizes the fuel
injectors. The ECM holds the fuel injectors de-
energized as long as the throttle remains above 80%
and the engine speed is below 800 RPM. If the throttle
position becomes less than 80%, the ECM again begins
to pulse the injectors "ON" and "OFF," allowing fuel into
the cylinders.

Deceleration Mode
The ECM reduces the amount of fuel injected when i
t
detects a decrease in the throttle position and the air
flow. When deceleration is very fast, the ECM may cu
t
off fuel completely for short periods.
Engine Speed/Vehicle Speed/Fuel Disable Mode
The ECM monitors engine speed. It turns off the fuel
injectors when the engine speed increase above 6400
RPM. The fuel injectors are turned back on when
engine speed decreases below 6150 RPM.

Fuel Cutoff Mode
No fuel is delivered by the fuel injectors when the
ignition is "OFF." This prevents engine run-on. In
addition, the ECM suspends fuel delivery if no reference
pulses are detected (engine not running) to preven
t
engine flooding.

Run Mode
The run mode has the following two conditions:

Open loop

Closed loop
When the engine is first started the system is in "open
loop" operation. In "open loop," the ECM ignores the
signal from the heated oxygen sensor (HO2S). I
t
calculates the air/fuel ratio based on inputs from the TP,
ECT, and MAF sensors.
The system remains in "open loop" until the following
conditions are met:

The HO2S has a varying voltage output showing
that it is hot enough to operate properly (this
depends on temperature).

The ECT has reached a specified temperature.


A specific amount of time has elapsed since
starting the engine.

Engine speed has been greater than a specified
RPM since start-up.
The specific values for the above conditions vary with
different engines and are stored in the programmable
read only memory (PROM). When these conditions are
met, the system enters "closed loop" operation. In
"closed loop," the ECM calculates the air/fuel ratio
(injector on-time) based on the signal from the HO2S.
This allows the air/fuel ratio to stay very close to 14.7:1.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-117
CIRCUIT DESCRIPTION
When the ignition switch is turned “ON," the Engine
Control Module (ECM) will turn “ON" the in-tank fuel
pump. The in-tank fuel pump will remain “ON" as long
as the engine is cranking or running and the ECM is
receiving 58X crankshaft position pulses. If there are no
58X crankshaft position pulses, the ECM will turn the
in-tank fuel pump “OFF" 2 seconds after the ignition
switch is turned “ON" or 2 seconds after the engine
stops running.
The in-tank fuel pump is an electric pump within an
integral reservoir. The in-tank fuel pump supplies fuel
through an in-line fuel filter to the fuel rail assembly. The
fuel pump is designed to provide fuel at a pressure
above the pressure needed by the fuel injectors. A fuel
pressure regulator, attached to the fuel rail, keeps the
fuel available to the fuel injectors at a regulated
pressure. Unused fuel is returned to the fuel tank by a
separate fuel return line.
TEST DESCRIPTION
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Connect the fuel pressure gauge to the fuel feed line
as shown in the fuel system illustration. Wrap a shop
towel around the fuel pressure connection in order to
absorb any fuel leakage that may occur when
installing the fuel pressure gauge. With the ignition
switch “ON" and the fuel pump running, the fuel
pressure indicated by the fuel pressure gauge
should be 333-376 kPa (3.4-3.8 kg/cm
2 / 48-55 psi).
This pressure is controlled by the amount o
f
pressure the spring inside the fuel pressure regulator
can provide.
3. A fuel system that cannot maintain a constant fuel
pressure has a leak in one or more of the following
areas:
 The fuel pump check valve.
 The fuel pump flex line.
 The valve or valve seat within the fuel pressure
regulator.
 The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using
a Tech 1 Tech 2. If an extremely lean condition
occurs, the oxygen sensor(s) will stop toggling. The
oxygen sensor output voltage(s) will drop below 500
mV. Also, the fuel injector pulse width will increase.

Important: Make sure the fuel system is not operating
in the “Fuel Cut-Off Mode."
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulato
r
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly
as the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine “OFF."
16.Check the spark plug associated with a particula
r
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. I
f
checking the spark plug associated with a particular
fuel injector for fouling or saturation does no
t
determine that a particular fuel injector is leaking,
use the following procedure:
 Remove the fuel rail, but leave the fuel lines and
injectors connected to the fuel rail. Refer to Fue
l
Rail Assembly in On-Vehicle Service.
 Lift the fuel rail just enough to leave the fuel
injector nozzles in the fuel injector ports.
CAUTION: In order to reduce the risk of fire and
personal injury that may result from fuel spraying
on the engine, verify that the fuel rail is positioned
over the fuel injector ports and verify that the fuel
injector retaining clips are intact.
 Pressurize the fuel system by connecting a 10
amp fused jumper between B+ and the fuel pump
relay connector.

Visually and physically inspect the fuel injector
nozzles for leaks.
17. A rich condition may result from the fuel pressure
being above 376 kPa (55 psi). A rich condition may
cause a DTC P0132 or a DTC P0172 to set.
Driveability conditions associated with rich conditions
can include hard starting (followed by black smoke)
and a strong sulfur smell in the exhaust.
20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure belo
w
333 kPa (48 psi). A lean condition may cause a DTC
P0131 or a DTC P0171 to set. Driveability conditions
associated with lean conditions can include hard
starting (when the engine is cold ), hesitation, poo
r
driveability, lack of power, surging , and misfiring.

6E-202 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0132 A O2 Sensor Circuit High
Voltage (Bank 1
Sensor 1) 15
P0152 A O2 Sensor Circuit High
Voltage (Bank 2
Sensor 1) 1. No DTC relating to ECT sensor, CMP sensor, CKP sensor,
VSS, injector control circuit, ignition control circuit and O2
sensor circuit no activity (bank 1 & 2).
2. Engine speed is between 1000rpm and 4000rpm.
3. Engine coolant temperature is between 70
and 110
.
4. Vehicle speed is between 0km/h and 120km/h.
5. Engine load is between 80% and 160%.
6. Throttle position fluctuation is below 0.28V.
7. O2 sensor bank 1 or bank 2 output voltage is below
600mV for 50 seconds. "Open Loop" fuel control.

CIRCUIT DESCRIPTION
The Engine Control Module (ECM) supplies a bias
voltage of about 450 mV between the heated oxygen
sensor (HO2S) signal high and signal low circuits. The
ECM constantly monitors the HO2S signal during
“closed loop" operation and compensates for a rich o
r
lean condition by decreasing or increasing injector pulse
width as necessary. If the HO2S voltage remains
excessively high for an extended period of time, DTC
P0132 or P0152 will be set.
DIAGNOSTIC AIDS
Check the following items:
 Fuel pressure – The system will go rich if pressure is
too high. The ECM can compensate for some
increase. However, if fuel pressure is too high, a DTC
P0132 or P0152 may be set. Refer to 6E-116 Fue
l
System Diagnosis.
 Perform “Injector Balance Test" – Refer to 6E-116
Fuel System Diagnosis.
 Check the canister for fuel saturation – If full of fuel,
check canister control and hoses.
 MAF sensor –The system can go rich if MAF senso
r
signal indicates an engine airflow measurement that
is not correct. Disconnect the MAF sensor to see it
the rich condition is corrected. If so, replace the MAF
sensor.

 Check for a leak in the fuel pressure regulato
r
diaphragm by checking the vacuum line to the
regulator for the presence of fuel. There should be no
fuel in the vacuum line.

An intermittent throttle position sensor output will
cause the system to go rich due to a false indication
of the engine accelerating.
 Shorted Heated Oxygen Sensor (HO2S) –If the
HO2S is internally shorted, the HO2S voltage
displayed on the Tech 2 will be over 1 volt. Try
disconnecting the affected HO2S with the key “ON,"
engine “OFF." If the displayed HO2S voltage
changes from over 1000 mV to around 450 mV,
replace the HO2S. Silicon contamination of the
HO2S can also cause a high HO2S voltage to be
indicated. This condition is indicated by a powdery
white deposit on the portion of the HO2S exposed to
the exhaust stream. If contamination is noticed,
replace the affected HO2S.
 Open HO2S Signal Circuit or Faulty HO2S–
A poor
connection or open in the HO2S signal circuit can
cause the DTC to set during deceleration fuel mode.
An HO2S which is faulty and not allowing a full
voltage swing between the rich and lean thresholds
can also cause this condition. Operate the vehicle by
monitoring the HO2S voltage with a Tech 2. If the
HO2S voltage is limited within a range between 300
mV to 600 mV, check the HO2S signal circuit wiring
and associated terminal conditions.
 If none of the above conditions are present, replace
the affected HO2S.