sensor ISUZU TROOPER 1998 Service Repair Manual

6E±41 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
EGR (Exhaust Gas Recirculation)
Diagnosis

A diagnosis of the EGR system is covered by DTC
P1403.

EGR VSV circuit diagnosis is covered by DTC P1404.

EGR pressure sensor diagnosis is covered by DTC
P405 and/or P406.

EGR EVRV circuit diagnosis is covered by DTC
P1405. Refer to the DTC charts.
Tech 2 Data Definitions and Ranges
A/C CLUTCH±Tech 2 Displays ON or OFF±
Indicates whether the A/C has commanded the A/C
clutch ON.
MAP kPa Ð Tech 2 Range 10-105 kPa/0.00-5.00
Volts Ð
The manifold absolute pressure reading is determined
from the MAP sensor signal monitored during key up and
wide open throttle (WOT) conditions. The manifold
absolute pressure is used to compensate for altitude
differences and is normally displayed around ª61-104º
depending on altitude and manifold absolute pressure.
CMP ACT. COUNTER ±Cam Position
DESIRED IDLE Ð Tech 2 Range 0-3187 RPM Ð
The idle speed that the ECM is commanding. The ECM
will compensate for various engine loads based on engine
coolant temperature, to keep the engine at the desired
speed.
ECT Ð (Engine Coolant Temperature) Tech 2
Range ±40
C to 151
C (±40
F to 304
F) Ð
The engine coolant temperature (ECT) is mounted in the
coolant stream and sends engine temperature
information to the ECM. The ECM applies 5 volts to the
ECT sensor circuit. The sensor is a thermistor which
changes internal resistance as temperature changes.
When the sensor is cold (high resistance), the ECM
monitors a high signal voltage and interprets that as a cold
engine. As the sensor warms (decreasing resistance),
the voltage signal will decrease and the ECM will interpret
the lower voltage as a warm engine.
ENGINE RUN TIME Ð Tech 2 Range
00:00:00-99:99:99 Hrs:Min:Sec Ð
Indicates the time elapsed since the engine was started.
If the engine is stopped, engine run time will be reset to
00:00:00.
ENGINE SPEED Ð Range 0-9999 RPM Ð
Engine speed is computed by the ECM from the 57X
reference input. It should remain close to desired idle
under various engine loads with engine idling.Air Intake Valve meter POSITION Ð Tech 2 Range
0-100 % Ð
IAT (INTAKE AIR TEMPERATURE)Ð Tech 2 Range
±40
C to 151
C (±40
F to 304
F) Ð
The ECM converts the resistance of the intake air
temperature sensor to degrees. Intake air temperature
(IAT) is used by the ECM to adjust fuel delivery and spark
timing according to incoming air density.
MAP Ð Tech 2 Range 10-105 kPa (0.00-4.97 Volts)Ð
The manifold absolute pressure (MAP) sensor measures
the change in the boost pressure.
MIL Ð Tech 2 Displays ON or OFF Ð
Indicates the ECM commanded state of the malfunction
indicator lamp.
AP Ð Tech 2 Range 0%-100% Ð
AP (Accelerator position) angle is computed by the ECM
from the AP sensor voltage. AP angle should display
ª0%º at idle and ª100%º at wide open throttle.
AP SENSOR Ð Tech 2 Range 0.00-5.00 Volts Ð
The voltage being monitored by the ECM on the AP
sensor signal circuit.
VEHICLE SPEEDÐTech 2 Range 0-255 km/h (0-155
mph)±
The vehicle speed sensor signal is converted into km/h
and mph for display.
Typical Scan Data Values
Use the Typical Scan Data Values Table only after the
On-Board Diagnostic System Check has been
completed, no DTC(s) were noted, and you have
determined that the on-board diagnostics are functioning
properly. Tech 2 values from a properly-running engine
may be used for comparison with the engine you are
diagnosing. The typical scan data values represent
values that would be seen on a normally-running engine.
NOTE: A Tech 2 that displays faulty data should not be
used, and the problem should be reported to the Tech 2
manufacturer. Use of a faulty Tech 2 can result in
misdiagnosis and unnecessary replacement of parts.
Only the parameters listed below are referred to in this
service manual for use in diagnosis. For further
information on using the Tech 2 to diagnose the ECM and
related sensors, refer to the applicable reference section
listed below. If all values are within the typical range
described below, refer to the
Symptoms section for
diagnosis.
Test Conditions
Engine running, lower radiator hose hot, transmission in
park or neutral, accessaries off, brake not applied and air
conditioning off.

6E±42
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
4JX1-TC Engine (Automatic and Manual Transmission)
Tech 2
Parameter
Data ListUnits
DisplayedTypical Data
Values (IDLE)Typical Data
Values
(2500 RPM)Refer To
Battery VoltageEngineVolts12.5 ~ 14.513 ~ 15General Description
Ignition StatusEngineOn/OffOnOnGeneral Description
Ignition Relay2EngineOn/OffOnOnGeneral Description
Idle SwitchEngineInactive/
ActiveÐÐDTC P0510, P1510
Manifold
Absolute
PressureEngineKPa96 ~ 106110 ~ 150General Description
DTC P0107, P0108
Rail Oil
PressureEngineMPa3.5 ~ 54.5 ~ 10General Description
DTC P0192, P0193
Desired Rail Oil
PressureEngineMPa4 ~ 55 ~ 9General Description
DTC P0192, P0193
Fuel
TemperatureEngine
C (
F)75 ~ 8575 ~ 85DTC P0182, P0183
Quick Warming
SwitchEngineOn/OffOffOffDTC P0380
Thermo RelayEngineOn/OffÐÐDTC P1655
Actual EGR
PressureEngineKPa58 ~ 60M/T 63 ~ 66
A/T 95 ~ 105DTC P0405, P0406
Barometric
PressureEngineKPa98 ~ 10298 ~ 102General Description
Relative EGR
PressureEngineKPa±38 ~ ±45M/T ±34 ~ ±37
A/T 0General Description
Desired EGR
PressureEngineKPa±43 ~ ±40M/T 36
A/T 0General Description
Brake SwitchEngineInactive/
ActiveÐÐDTC P1588
GearEngineÐÐÐÐ
Vehicle SpeedEngineKm/h00Transmission Diagnosis
Rail Pressure
Control ValveEngine%17 ~ 2218 ~ 27DTC P1193
EGR StatusEngineDisable/
EnableEnableM/T Enable
A/T DisableGeneral Description
EGR Switching
ValveEngineOn/OffÐÐGeneral Description
Throttle Motor
Position SensorEngineVolts3.1 ~ 3.90.2 ~ 0.9DTC P1485, P1486,
P1487
Throttle Motor
PositionEngineSteps
0 ~ 1.00 ~ 1.0
DTC P1488
Delirered Fuel
QuantityEnginemm 3/st
6 ~ 106 ~ 12
General Description
Injector StatusEngineDisable/
EnableEnableEnableDTC P0201, P0202,
P0203, P0204, General
Description
Injector Pulse
WidthEnginems0.9 ~ 1.250.7 ~ 1.1General Description
Injector Start
OffsetEngine
CAÐÐGeneral Description

6E±48
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Malfunction Indicator Lamp (MIL) ªONº Steady

StepActionValue(s)Ye sNo
1Was the ªOn-Board diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªOFF,º disconnect ECM.
2. Ignition ªON,º observe the MIL (CHECK ENGINE
lamp).
Is the MIL ªON?º
ÐGo to Step 3Go to Step 5
31. Ignition ªOFF,º disconnect the instrument panel
cluster.
2. Check the MIL driver circuit between the ECM and
the instrument panel cluster for a short to ground.
3. If a problem is found, repair as necessary.
Was the MIL driver circuit shorted to ground?
Ð
Go to OBD
System
Check
Go to Step 4
4Replace the instrument panel cluster.
Is the action complete?
Ð
Go to OBD
System
Check
Ð
51. Ignition ªOFF,º reconnect the ECM.
2. Ignition ªON,º reprogram the ECM. Refer to
On-Vehicle Service in Engine Control Module and
Sensor
for procedures.
3. Using the Tech 2 output controls function, select
MIL dash lamp control and command the MIL
ªOFF.º
Did the MIL turn ªOFF?º
Ð
Go to OBD
System
Check
Go to Step 6
6Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
Ð
Go to OBD
System
Check
Ð

6E±49 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run
Circuit Description
In this type of injector system, the Engine Control Module
(ECM) triggers the correct driver inside the injector, which
then triggers the correct injector based on the 57X signal
received from the crankshaft position sensor (CKP).
During crank, the ECM monitors the CKP 57X signal. The
CKP signal is used to determine which cylinder will fire
first. After the CKP 57X signal has been processed by the
ECM, it will command all four injectors to allow a priming
shot of fuel for all the cylinders. After the priming, the
injectors are left ªOFFº during the next four 57X reference
pulses from the CKP. This allows each cylinder a chance
to use the fuel from the priming shot. During this waiting
period, a camshaft position (CMP) signal pulse will have
been received by the ECM. The CMP signal allows the
ECM to operate the injectors sequentially based on
camshaft position. If the camshaft position signal is not
present at start-up, the ECM will begin sequential fuel
delivery with a 1-in-4 chance that fuel delivery is correct.
The engine will run without a CMP signal, but will set a
DTC code.
Diagnostic Aids
An intermittent problem may be caused by a poor
connection, rubbed-through wire insulation or a wirebroken inside the insulation. Check for the following
items:

Poor connection or damaged harness ± Inspect the
ECM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal-to-wore connection, and
damaged harness.

Faulty engine coolant temperature sensor ± Using a
Tech 2, compare engine coolant temperature with
manifold air temperature on a completely cool engine.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
4. An obvious cause of low fuel pressure would be an
empty fuel tank.
5. The engine will easily start and run if a few injectors
are disabled. It is not necessary to test all injectors
at this time since this step is only a test to verify that
all of the injectors have not been disabled by fuel
contamination.
8.If there is an open or shorted driver circuit, DTCs
0201-0204 should be set.
Engine Cranks But Will Not Run

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Check the 15 A injector fuse, the 15 A engine device
fuse, and the 15A ECM fuse.
Was a fuse blown?
ÐGo to Step 3Go to Step 4
3Check for a short to ground and replace the fuse.
Is the action complete?
ÐVerify repairÐ
4Is fuel tank empty?
Ð
Fill the fuel
tank
Go to Step 5
5Is the right fuel using?
ÐGo to Step 6
Replace the
fuel
6Is the right engine oil using?
ÐGo to Step 7
Replace the
engine oil
7Using the Tech±2.
Is DTC P0192 or P0193 set? (Check rail pressure
system)
Ð
Go to DTC
P0192 or
DTC P0193
Go to Step 8
8Using the Tech±2.
Is DTC P0201 ± P0204 set? (Check inject circuit fault)
Ð
Go to DTC
P0201 ±
P0204
Go to Step 9
9Using the Tech±2.
Is DTC P1657 set? (Check ECM Main relay)
Ð
Go to DTC
P1657
Go to Step 10

6E±50
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run

 
StepNo Ye s Value(s) Action
10Refer to Engine Mechanical Diagnosis to diagnose the
following conditions:

Faulty camshaft drive belts

Leaking or sticky valves or rings

Excessive valve deposits

Weak valve springs

Incorrect valve timing

Leaking head gasket
Is the action complete?
ÐVerify repairGo to Step 11
11Observe the ªEngine Speedº data display on the Tech 2
while cranking the engine.
Is the engine RPM indicated? (If the Tech 2 is normally
powered from the cigarette lighter socket, and if the
Tech 2 display goes blank while cranking the engine, it
will be necessary to power the Tech 2 directly from the
vehicle battery.)
ÐGo to Step 12Go to Step 17
121. At the ECM (female) side of the connector
mentioned in step, connect a test light between the
ignition + terminal and one of the injector driver
circuits at the same connector.
2. Ignition ªON.º
3. Observe the test light, and repeat the test for each
injector driver circuit by oscilloscope.
Did the test light stay on when checking any of the 4
injector driver circuits?
ÐGo to Step 13Go to Step 15
131. Ignition ªOFF,º disconnect the ECM.
2. Ignition ªON,º observe the test light.
Is the test light ªON?º
ÐGo to Step 14Go to Step 16
14Locate and repair the short to ground in the injector
driver circuit.
Is the action complete?
ÐVerify repairÐ
15Check for an open injector driver circuit.
Was a problem found?
ÐVerify repairGo to Step 16
16Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
ÐVerify repairÐ
171. Raise the vehicle and disconnect the CKP sensor
harness.
2. Ignition ªON.º
3. With a test light to ground, probe the harness
ignition feed terminal.
Did the light illuminate?
ÐGo to Step 19Go to Step 18
18Check the ignition feed wire between the sensor and
the ECM for a short to ground or open circuit.
Is the action complete?
ÐVerify repairÐ

6E±51 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run

 
StepNo Ye s Value(s) Action
191. Ignition ªON.º
2. At the CKP harness connector, connect a test light
between the ignition and ground terminals.
Did the light illuminate?
ÐGo to Step 21Go to Step 20
20Check the sensor ground circuit for an open or short to
voltage.
Is the action complete?
ÐVerify repairÐ
21Check the signal circuit between the sensor and the
ECM for a short to ground, short to voltage, or an open.
Was a problem found?
ÐVerify repairGo to Step 22
22Replace the CKP sensor.
Is the action complete?
ÐVerify repairGo to Step 16

6E±54
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
ECM Diagnostic Trouble Codes
The following table lists the diagnostic trouble codes
supported a Tech 2 and to flash.If any DTCs not listedhere are displayed by a Tech 2, the Tech 2 data may be
faulty; notify the Tech 2 manufacturer of any DTCs
displayed that are not included in the following table.
ECM Diagnostic Trouble Codes
DTC
using a
Tech 2
Flash DTCDescriptionMIL
P010734MAP Sensor Low VoltageON
P010834MAP Sensor High VoltageON
P011223Intake Air temp Sensor Low VoltageON
P011323Intake Air temp Sensor High VoltageON
P011714Engine Coolant Temp Sensor Low VoltageON
P011814Engine Coolant Temp Sensor High VoltageON
P012133Accel Position Sensor RationalityON
P012221Accel Position Sensor Low VoltageON
P012321Accel Position Sensor High VoltageON
P018215Fuel Temp Sensor Low VoltageON
P018315Fuel Temp Sensor High VoltageON
P019263Rail Pressure Sensor Low VoltageON
P019363Rail Pressure Sensor High VoltageON
P119364RPCV Circuit Open/ShortÐ
P119461Rail Pressure System Low VoltageON
P119561Rail Pressure System High VoltageON
P119662Rail Pressure System High WarningON
P019716Oil Temp sensor Low VoltageON
P019816Oil Temp sensor High VoltageON
P020151Injector #1 Circuit FaultON
P020252Injector #2 Circuit FaultON
P020353Injector #3 Circuit FaultON
P020454Injector #4 Circuit FaultON
P021722High Coolant Temp WarningON
P121736High Oil Temp WarningON
P021911Engine Over Speed WarningON
P033643Crank Position Sensor Out of SyncroON
P033743Crank Position Sensor No SignalON
P034141Cam Position Sensor Out of SyncroON
P034241Cam Position Sensor No SignalON
P038066Glow Relay Circuit Open/ShortÐ
P038167Glow Lamp Circuit Open/ShortÐ
P140332EGR EVRV FaultÐ
P140431EGR VSV CircuitÐ
P040526EGR Pressure Sensor Low VoltageON
P140537EGR EVRV Circuit Open/ShortÐ
P040626EGR Pressure Sensor High VoltageON

6E±55 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
DTC
using a
Tech 2Flash DTCDescriptionMIL
P047571EXH #1 VSV Circuit Open/ShortÐ
P147571EXH #2 VSV Circuit Open/ShortÐ
P148574Intake Throttle Position Sensor Low VoltageON
P148674Intake Throttle Position Sensor High VoltageON
P148773Intake Throttle System Circuit Open/ShortON
P148872Intake Throttle Motor Control Circuit Signal GapÐ
P050224Vehicle Speed Sensor No SignalON
P051075Idle SW Malfunction, Open CircuitON
P151075Idle SW Malfunction, Short CircuitON
P056235System Voltage Too LowON
P156235System Voltage Too Low at CrankingON
P158725Brake SW Malfunction [B]Ð
P158825Brake SW Malfunction [A]ON
P060155ECM Checksum ErrorON
P162656Immobilizer No SignalON
P163156Immobilizer Wrong SignalON
P164856No Security Code EnteredON
P164956Immobilizer Function not ProgrammedON
P065077Check Engine Lamp Circuit Open/ShortÐ
P065427Techometer Circuit Open/ShortÐ
P165517Thermo Relay Circuit Open/ShortÐ
P165776ECM Main Relay Circuit Open/ShortÐ
P158947TransMission SW Circuit Open/ShortÐ

6E±56
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0107 (Flash DTC 34)
MAP Sensor Circuit Low Voltage
060RW134
Circuit Description
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum).
The ECM monitors the MAP signals for voltages outside
the normal range of the MAP sensor. If the ECM detects a
MAP signal voltage that is excessively low, DTC P0107
will be set.
Action Taken When the DTC Sets

The ECM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.

The ECM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

DTC P0107 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the ECM battery
feed.
Diagnostic Aids
Check for the following conditions:

Turn on the ignition switch and stop the engine. At this
time, the boost pressure will be equal to the
atmospheric pressure and the signal voltage will
increase.

Check for intermittent codes.

The MAP sensor shares a ground with the ECT sensor,
and the Transmission Fluid Temperature sensor.

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

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
MAP display on the Tech 2 while moving connectors
and wiring harnesses related to the sensor. A change
in the display will indicate the location of the fault.
If DTC P0107 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC P0107 Diagnostic Chart may isolate
the cause of the fault.

6E±57 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
DTC P0107 ± MAP Sensor Circuit Low Voltage

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Put the engine into an idling status.
Is the MAP voltage value displayed on the Tech 2 below
the specified value?
0.25 VGo to Step 3
Refer to
Diagnostic
Aids
and
Symptom
Diagnosis
31. Turn off the ignition switch.
2. Remove the sensor connector connection.
3. Jumper between harness pins ªredº and ªblueº
wires.
4. Turn on the ignition switch ªONº.
Is the MAP voltage reading above the specified value?
4 VGo to Step 5Go to Step 4
41. Turn off the ignition switch.
2. Remove the jumper wire.
3. Connect the relay & solenoid checker
(5-8840-0386-0) to the battery voltage, then check
the MAP signal circuit (blue wire).
4. Turn on the ignition switch.
Is the value displayed on the Tech 2 above the specified
value?
4 VGo to Step 6Go to Step 7
5Check the terminal connection at the MAP sensor and
repair or replace terminal if necessary.
Is the action complete?
ÐVerify repairÐ
6Repair the 5V power circuit (red) harness or Replace
the ECM (Refer to the Data Programming in Case of
ECM change).
Is the action complete?
ÐVerify repairÐ
7Repair the signal circuit (blue) harness or Replace the
ECM (Refer to the Data Programming in Case of ECM
change).
Is the action complete?
ÐVerify repairÐ