1998 ISUZU TROOPER check oil

6D3±18STARTING AND CHARGING SYSTEM
Charging System
General Description
The IC integral regulator charging system and its main
components are connected as shown in the 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.
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 ªONº 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
ªONº position and observe the warning lamp.
If lamp does not come on:
Disconnect wiring connector from generator, and
ground the terminal ªLº on connector side.
If lamp comes on:
Repair or replace the generator.
F06RW009

6D3±24STARTING AND CHARGING SYSTEM
Stator Coil
1. Measure resistance between respective phases.
2. Measure insulation resistance between stator coil
and core with a mega±ohmmeter.
If less than standard, replace the coil.
066RS018
Brush
Measure the brush length.
If more than limit, replace the brush.
Standard: 10.mm (0.4134 in)
Limit: 8.4.mm (0.3307 in)
066RS019
Rectifier Assembly
Check for continuity across ªPº and ªEº in the y 100W
range of multimeter.
066RW002Change polarity, and make sure that there is continuity in
one direction, and not in the reverse direction. In case of
continuity in both directions, replace the rectifier
assembly.
IC Regulator Assembly
Check for continuity across ªBº and ªFº in the y 100W
range of multimeter.
066RS021Change polarity, and make sure that there is continuity in
one direction, and not in the reverse direction. In case of
continuity in both directions, replace the IC regulator
assembly.
Reassembly
To reassemble, follow the disassembly steps in the
reverse order, noting the following points:

6E±2
ENGINE DRIVEABILITY AND EMISSIONS
Primary System-Based Diagnostic 6E±50. . . . . . . . .
Primary System-Based Diagnostic 6E±50. . . . . . .
Fuel Control Heated Oxygen Sensor 6E±50. . . . .
HO2S Heater 6E±50. . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Trim System Monitor Diagnostic
Operation 6E±50. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Trim System Monitor Diagnostic
Operation 6E±50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Trim Cell Diagnostic Weights 6E±50. . . . . . .
On-Board Diagnostic (OBD) System Check 6E±51.
A/C Clutch Control Circuit Diagnosis 6E±54. . . . . . .
Electronic Ignition System Diagnosis 6E±60. . . . . . .
Fuel Metering System Check 6E±60. . . . . . . . . . . . .
Idle Air Control (IAC) Valve 6E±60. . . . . . . . . . . . . . .
Fuel System Pressure Test 6E±60. . . . . . . . . . . . . . .
Fuel Injector Coil Test Procedure and Fuel
Injector Balance Test Procedure 6E±60. . . . . . . . . .
Knock Sensor Diagnosis 6E±65. . . . . . . . . . . . . . . . .
Powertrain Control Module (PCM) Diagnosis 6E±65
Multiple PCM Information Sensor DTCS Set 6E±65
Exhaust Gas Recirculation (EGR) Diagnosis
(For except EXPORT and
SOUTH AFRICA) 6E±68. . . . . . . . . . . . . . . . . . . . . . .
Engine Tech 2 Data Definitions and Ranges 6E±68
Typical Scan Data Values 6E±70. . . . . . . . . . . . . . . .
No Malfunction Indicator Lamp (MIL) 6E±74. . . . . . .
Malfunction Indicator Lamp (MIL) ªONº
Steady 6E±77. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Cranks But Will Not Run 6E±79. . . . . . . . . . .
Fuel System Electrical Test 6E±85. . . . . . . . . . . . . . .
Fuel System Diagnosis 6E±88. . . . . . . . . . . . . . . . . . .
Idle Air Control (IAC) System Check 6E±93. . . . . . .
Knock Sensor (KS) System Check
(Engine Knock, Poor Performance, or Poor
Economy) 6E±95. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Gas Recirculation (EGR) System
Check 6E±97. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manifold Absolute Pressure (MAP) Output
Check 6E±99. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PCM Diagnostic Trouble Codes 6E±101. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0101
MAF System Performance 6E±104. . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0102
MAF Sensor Circuit Low Frequency 6E±107. . . . . .
Diagnostic Trouble Code (DTC) P0103
MAF Sensor Circuit High Frequency 6E±110. . . . . .
Diagnostic Trouble Code (DTC) P0107
MAP Sensor Circuit Low Voltage 6E±112. . . . . . . . . .
Diagnostic Trouble Code (DTC) P0108
MAP Sensor Circuit High Voltage 6E±115. . . . . . . . .
Diagnostic Trouble Code (DTC) P0112
IAT Sensor Circuit Low Voltage 6E±118. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0113
IAT Sensor Circuit High Voltage 6E±121. . . . . . . . . . Diagnostic Trouble Code (DTC) P0117
ECT Sensor Circuit Low Voltage 6E±124. . . . . . . . . .
Diagnostic Trouble Code (DTC) P0118
ECT Sensor Circuit High Voltage 6E±127. . . . . . . . .
Diagnostic Trouble Code (DTC) P0121
TP System Performance 6E±130. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0122
TP Sensor Circuit Low Voltage 6E±133. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0123
TP Sensor Circuit High Voltage 6E±136. . . . . . . . . .
Diagnostic Trouble Code (DTC) P0131
HO2S Circuit Low Voltage Bank 1
Sensor 1 6E±139. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0132
HO2S Circuit High Voltage Bank 1
Sensor 1 6E±142. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0134
HO2S Circuit Insufficient Activity Bank 1
Sensor 1 6E±145. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0151
HO2S Circuit Low Voltage Bank 2
Sensor 1 6E±148. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0152
HO2S Circuit HIGH Voltage Bank 2
Sensor 1 6E±151. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0171
Fuel Trim System Lean Bank 1 6E±154. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0172
Fuel Trim System Rich Bank 1 6E±158. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0174
Fuel Trim System Lean Bank 2 6E±162. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0175
Fuel Trim System Rich Bank 2 6E±166. . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0201
Injector 1 Control Circuit 6E±170. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0202
Injector 2 Control Circuit 6E±173. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0203
Injector 3 Control Circuit 6E±176. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0204
Injector 4 Control Circuit 6E±179. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0205
Injector 5 Control Circuit 6E±182. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0206
Injector 6 Control Circuit 6E±185. . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0325
KS Module Circuit 6E±188. . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0327
KS Sensor Circuit 6E±190. . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0336
58X Reference Signal Circuit 6E±193. . . . . . . . . . . . .
Diagnostic Trouble Code (DTC) P0337
CKP Sensor Circuit Low Frequency 6E±195. . . . . . .
Diagnostic Trouble Code (DTC) P0341
CMP Sensor Circuit Performance 6E±198. . . . . . . . .
Diagnostic Trouble Code (DTC) P0342
CMP Sensor Circuit Low 6E±202. . . . . . . . . . . . . . . . .

6E±38
ENGINE DRIVEABILITY AND EMISSIONS
General Service Information
OBD Serviceablity Issues
The list of non-vehicle faults that could affect the
performance of the OBD system has been compiled.
These non-vehicle faults vary from environmental
conditions to the quality of fuel used.
The illumination of the MIL (ªCheck Engineº lamp) due to
a non-vehicle fault could lead to misdiagnosis of the
vehicle, increased warranty expense and customer
dissatisfaction. The following list of non-vehicle faults
does not include every possible fault and may not apply
equally to all product lines.
Fuel Quality
Using fuel with the wrong octane rating for your vehicle
may cause driveability problems. Many of the major fuel
companies advertise that using ªpremiumº gasoline will
improve the performance of your vehicle. Most premium
fuels use alcohol to increase the octane rating of the fuel.
Although alcohol-enhanced fuels may raise the octane
rating, the fuel's ability to turn into vapor in cold
temperatures deteriorates. This may affect the starting
ability and cold driveability of the engine.
Low fuel levels can lead to fuel starvation, lean engine
operation, and eventually engine misfire.
Non-OEM Parts
All of the OBD diagnostics have been calibrated to run
with OEM parts. Something as simple as a
high-performance exhaust system that affects exhaust
system back pressure could potentially interfere with the
operation of the EGR valve and thereby turn on the MIL
(ªCheck Engineº lamp). Small leaks in the exhaust
system near the post catalyst oxygen sensor can also
cause the MIL (ªCheck Engineº lamp) to turn on.
Aftermarket electronics, such as cellular phones,
stereos, and anti-theft devices, may radiate EMI into the
control system if they are improperly installed. This may
cause a false sensor reading and turn on the MIL (ªCheck
Engineº lamp).
Environment
Temporary environmental conditions, such as localized
flooding, will have an effect on the vehicle ignition system.
If the ignition system is rain-soaked, it can temporarily
cause engine misfire and turn on the MIL (ªCheck Engineº
lamp).
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the MIL
(ªCheck Engineº lamp) to turn on if the vehicle is not
maintained properly. Restricted air filters, fuel filters, and
crankcase deposits due to lack of oil changes or improper
oil viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD. Poor vehicle
maintenance can not be classified as a ªnon-vehicle
faultº, but with the sensitivity of OBD diagnostics, vehicle
maintenance schedules must be more closely followed.Related System Faults
Many of the OBD system diagnostics will not run if the
PCM detects a fault on a related system or component.
One example would be that if the PCM detected a Misfire
fault, the diagnostics on the catalytic converter would be
suspended until Misfire fault was repaired. If the Misfire
fault was severe enough, the catalytic converter could be
damaged due to overheating and would never set a
Catalyst DTC until the Misfire fault was repaired and the
Catalyst diagnostic was allowed to run to completion. If
this happens, the customer may have to make two trips to
the dealership in order to repair the vehicle.
Maintenance Schedule
Refer to the Maintenance Schedule.
Visual / Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any diagnostic
procedure or diagnosing the cause of an emission test
failure. This can often lead to repairing a problem without
further steps. Use the following guidelines when
performing a visual/physical inspection:

Inspect all vacuum hoses for punches, cuts,
disconnects, and correct routing.

Inspect hoses that are difficult to see behind other
components.

Inspect all wires in the engine compartment for proper
connections, burned or chafed spots, pinched wires,
contact with sharp edges or contact with hot exhaust
manifolds or pipes.
Basic Knowledge of Tools Required
NOTE: Lack of basic knowledge of this powertrain when
performing diagnostic procedures could result in an
incorrect diagnosis or damage to powertrain
components. Do not attempt to diagnose a powertrain
problem without this basic knowledge.
A basic understanding of hand tools is necessary to effec-
tively use this section of the Service Manual.
Serial Data Communications
Class II Serial Data Communications
This vehicle utilizes the ªClass IIº communication system.
Each bit of information can have one of two lengths: long
or short. This allows vehicle wiring to be reduced by
transmitting and receiving multiple signals over a single
wire. The messages carried on Class II data streams are
also prioritized. If two messages attempt to establish
communications on the data line at the same time, only
the message with higher priority will continue. The device
with the lower priority message must wait. The most
significant result of this regulation is that it provides Tech 2
manufacturers with the capability to access data from any
make or model vehicle that is sold.

6E±54
ENGINE DRIVEABILITY AND EMISSIONS
A/C Clutch Control Circuit Diagnosis
D06RW085
Circuit Description
When air conditioning and blower fan are selected, and if
the system has a sufficient refrigerant charge, a 12-volt
signal is supplied to the A/C request input of the
powertrain control module (PCM). The A/C request
signal may be temporarily canceled during system
operation by the electronic thermostat in the evaporator
case. The electronic thermostat may intermittently
remove the control circuit ground for the A/C thermostat
relay to prevent the evaporator from forming ice. When
the A/C request signal is received by the PCM, the PCM
supplies a ground from the compressor clutch relay if the
engine operating conditions are within acceptable
ranges. With the A/C compressor relay energized,
voltage is supplied to the compressor clutch coil.
The PCM will enable the compressor clutch to engage
whenever A/C has been selected with the engine running,
unless any of the following conditions are present:
The throttle is greater than 90%.

The ignition voltage is below 10.5 volts.

The engine speed is greater than 4500 RPM for 5
seconds or 5400 RPM.

The engine coolant temperature (ECT) is greater than
125
C (257
F).

The intake air temperature (IAT) is less than 5
C
(41
F).

The power steering pressure switch signals a cramped
position.
Diagnostic Aids
To diagnose an the intermittent fault, check for the
following conditions:

Poor connection at the PCM±Inspect connections for
backed-out terminals, improper mating, broken locks,
improperly formed or damaged terminals, and poor
terminal-to-wire connection.

6E±60
ENGINE DRIVEABILITY AND EMISSIONS
Electronic Ignition System Diagnosis
If the engine cranks but will not run or immediately stalls,
the Engine Cranks But Will Not Start chart must be used
to determine if the failure is the ignition system or the fuel
system. If DTC P0341, or P0336 is set, the appropriate
diagnostic trouble code chart must be used for diagnosis.
If a misfire is being experienced with no DTC set, refer to
the
Symptoms section for diagnosis.
Fuel Metering System Check
Some failures of the fuel metering system will result in an
ªEngine Cranks But Will Not Runº symptom. If this
condition exists, refer to the
Cranks But Will Not Run
chart. This chart will determine if the problem is caused
by the ignition system, the PCM, or the fuel pump
electrical circuit.
Refer to
Fuel System Electrical Test for the fuel system
wiring schematic.
If there is a fuel delivery problem, refer to
Fuel System
Diagnosis
, which diagnoses the fuel injectors, the fuel
pressure regulator, and the fuel pump. If a malfunction
occurs in the fuel metering system, it usually results in
either a rich HO2S signal or a lean HO2S signal. This
condition is indicated by the HO2S voltage, which causes
the PCM to change the fuel calculation (fuel injector pulse
width) based on the HO2S reading. Changes made to the
fuel calculation will be indicated by a change in the long
term fuel trim values which can be monitored with a Tech
2. Ideal long term fuel trim values are around 0%; for a
lean HO2S signal, the PCM will add fuel, resulting in a fuel
trim value above 0%. Some variations in fuel trim values
are normal because all engines are not exactly the same.
If the fuel trim values are greater than +23%, refer to
DTC
P0131, DTC P0151, DTC P0171, and DTC 1171
for items
which can cause a lean HO2S signal.
Idle Air Control (IAC) Valve
The Tech 2 displays the IAC pintle position in counts. A
count of ª0º indicates the PCM is commanding the IAC
pintle to be driven all the way into a fully-seated position.
This is usually caused by a large vacuum leak.
The higher the number of counts, the more air is being
commanded to bypass the throttle blade. Refer to IAC
System Check in order to diagnose the IAC system.
Refer to
Rough, Unstable, or Incorrect Idle, Stalling in
Symptoms for other possible causes of idle problems.
Fuel System Pressure Test
A fuel system pressure test is part of several of the
diagnostic charts and symptom checks. To perform this
test, refer to
Fuel Systems Diagnosis.
Fuel Injector Coil Test Procedure and
Fuel Injector Balance Test Procedure
T32003
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Relieve the fuel pressure by connecting the
5-8840-0378-0 Fuel Pressure Gauge to the fuel
pressure connection on the fuel rail.
CAUTION: In order to reduce the risk of fire and
personal injury, wrap a shop towel around the fuel
pressure connection. The towel will absorb any fuel
leakage that occurs during the connection of the fuel
pressure gauge. Place the towel in an approved
container when the connection of the fuel pressure
gauge is complete.
Place the fuel pressure gauge bleed hose in an
approved gasoline container.
With the ignition switch ªOFF,º open the valve on the
fuel pressure gauge.
3. Record the lowest voltage displayed by the DVM
after the first second of the test. (During the first
second, voltage displayed by the DVM may be
inaccurate due to the initial current surge.)
Injector Specifications:
Resistance Ohms
Voltage Specification at
10
C-35
C (50
F-95
F)
11.8 ± 12.65.7 ± 6.6

The voltage displayed by the DVM should be within
the specified range.

The voltage displayed by the DVM may increase
throughout the test as the fuel injector windings
warm and the resistance of the fuel injector windings
changes.

6E±61 ENGINE DRIVEABILITY AND EMISSIONS

An erratic voltage reading (large fluctuations in
voltage that do not stabilize) indicates an
intermittent connection within the fuel injector.
5. Injector Specifications:
Highest Acceptable
Voltage Reading
Above/Below 35
C/10
C
(95
F/50
F)
Acceptable Subtracted
Value
9.5 Volts0.6 Volts
7. The Fuel Injector Balance Test portion of this chart
(Step 7 through Step 11) checks the mechanical
(fuel delivery) portion of the fuel injector. An engine
cool-down period of 10 minutes is necessary in
order to avoid irregular fuel pressure readings due
to ªHot Soakº fuel boiling.
Injector Coil Test Procedure (Steps 1-6) and Injector Balance Test Procedure (Steps 7-11)
R262001
CYLINDER123456
1st Reading (1)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)296 kPa
(43 psi)
2nd Reading (2)131 kPa
(19 psi)117 kPa
(17 psi)124 kPa
(18 psi)145 kPa
(21 psi)131 kPa
(19 psi)130 kPa
(19 psi)
Amount of Drop (1st
Reading±2nd Reading)165 kPa
(24 psi)179 kPa
(26 psi)172 kPa
(25 psi)151 kPa
(22 psi)165 kPa
(24 psi)166 kPa
(24 psi)
Av.drop = 166 kPa/24 psi +
10 kPa/1.5 psi
= 156 ± 176 kPa or
22.5 ± 25.5 psiOKFaulty, Rich
(Too Much
Fuel Drop)OKFaulty, Lean
(Too Little
Fuel Drop)OKOK
NOTE: These figures are examples only.

6E±62
ENGINE DRIVEABILITY AND EMISSIONS
Injector Coil Test Procedure (Steps 1-6) and Injector Balance Test Procedure
(Steps 7-11)

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Turn the engine ªOFF.º
NOTE: In order to prevent flooding of a single cylinder
and possible engine damage, relieve the fuel pressure
before performing the fuel injector coil test procedure.
2. Relieve the fuel pressure. Refer to
Test Description
Number 2.
3. Connect the 5-8840-2638-0 Fuel Injector Tester to
B+ and ground, and to the 5-8840-2619-0 Injector
Switch Box.
4. Connect the injector switch box to the grey fuel
injector harness connector located on the front of
the EVAP canister bracket.
5. Set the amperage supply selector switch on the fuel
injector tester to the ªCoil Testº 0.5 amp position.
6. Connect the leads from the 5-8840-0285-0 Digital
Voltmeter (DVM) to the injector tester. Refer to the
illustrations associated with the test description.
7. Set the DVM to the tenths scale (0.0).
8. Observe the engine coolant temperature.
Is the engine coolant temperature within the specified
values?
10
C (50
F)
to 35
C
(95
F)
Go to Step 3Go to Step 5
31. Set injector switch box injector #1.
2. Press the ªPush to Start Testº button on the fuel
injector tester.
3. Observe the voltage reading on the DVM.
IMPORTANT:The voltage reading may rise during the
test.
4. Record the lowest voltage observed after the first
second of the test.
5. Set the injector switch box to the next injector and
repeat steps 2, 3, and 4.
Did any fuel injector have an erratic voltage reading
(large fluctuations in voltage that did not stabilize) or a
voltage reading outside of the specified values?
5.7-6.6 VGo to Step 4Go to Step 7
4Replace the faulty fuel injector(s). Refer to Fuel
Injector.
Is the action complete?ÐGo to Step 7Ð