1998 ISUZU TROOPER fuse

6E±93 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description
The rail pressure control valve (RPCV) is built in the high
pressure oil circuit.
RPCV is an important device which is used to control oil
pressure in the HEUI system.
The circuit receives current through Engine 15A fuse from
the battery, current flowing in the order of RPCV.
Action Taken When the DTC Sets

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 P1196 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:
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
Rail Pressure Control display on the Tech 2 while
moving connectors and wiring harnesses related to the
Rail Pressure Control. A change in the Rail Pressure
Control display will indicate the location of the fault.
If DTC P1196 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.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is present.
DTC P1196 ± RP System High Warning

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Engine is running.
2. Observe the ªRail Pressure Controlº display on the
Tech 2.
Is the action correct?
ÐGo to Step 4Go to Step 3
3Replace the RPCV.
Is the action complete?
ÐVerify repairGo to Step 4
41. Engine is running.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ª DTCº info for DTC P1196.
Does the Tech 2 indicate DTC P1196 failed this
ignition?
ÐGo to Step 5Ð
51. Check the 2 way valve.
2. Observe the ªRP Controlº display on the Tech 2.
Is the action correct?
ÐGo to Step 4Go to Step 6
6Replace the 2 way valve.
Is the action complete?
ÐVerify repairÐ

6E±126
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0380 (Flash DTC 66)
Glow Relay Circuit Open/Short
060RW132
Circuit Description
Glow relay circuit receives current through Glow 50A fuse
from the battery. Glow relay is circuited to Glow plug.
Action Taken When the DTC Sets

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 P0380 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the ECM battery
feed.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation. Check for:

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

Damaged harness ± Inspect the wiring harness for
damage.

6E±127 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
DTC P0380 ± Glow Relay Circuit Open/Short

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Attempt to start the engine.
Does the engine start?
ÐGo to Step 3Go to Chart 3
31. Review and record Failure Records information.
2. Clear DTC P0380.
3. Start the engine and idle for 1 minute.
4. Observe DTCs.
Is DTC P0380 set?
ÐGo to Step 4
Refer to
Diagnostic
Aid
4Check the glow fuse 50A.
Is the glow fuse 50A damage?
ÐGo to Step 5Go to Step 6
5Replace the glow fuse 50A.
Is the action complete?
ÐVerify repairGo to Step 6
61. Ignition ªOFF.º
2. Check for an open or a short to ground in the Glow
relay circuit between the Glow relay connector and
the ECM harness connector.
3. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 7
7Check the connections at the Glow relay and replace
the terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 8
8Replace the Glow relay.
Is the action complete?
ÐVerify repairGo to Step 9
9Check the connections at the ECM and replace the
terminals if necessary.
Did any terminals require replacement?
ÐVerify repair Go to Step 10
10Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
ÐVerify repairÐ

6E±128
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0381 (Flash DTC 67)
Glow Lamp Circuit Open/Short
060RW136
Circuit Description
Glow Lamp Circuit receives current through Meter 10A
fuse, Glow lamp being circuited to ECM.
Action Taken When the DTC Sets

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 P0381 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the ECM battery
feed.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation. Check for:

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

Damaged harness ± Inspect the wiring harness for
damage.

6E±140
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0475 (Flash DTC 71)
EXH #1 VSV Circuit
060RW135
Circuit Description
EXH. #1, #2 VSV Circuit receives current through Engine
15A fuse, #1 and #2 being connected in parallel.
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 P0475 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:

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.

6E±142
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1475 (Flash DTC 71)
EXH #2 VSV Circuit Open/Short
060RW135
Circuit Description
EXH. #1, #2 VSV Circuit receives current through Engine
15A fuse, #1 and #2 being connected in parallel.
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 P1475 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:

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.

6E±152
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0502 (Flash DTC 24)
VSS (Vehicle Speed Sensor) No Signal
060RW136
Circuit Description
The vehicle speed sensor has a magnet rotated by the
transmission output shaft. Attached to the sensor is a hall
effect circuit the interacts with the magnetic field treated
by the rotating magnet. A 12-volt operating supply for the
speed sensor hall circuit is supplied from the meter fuse.
The VSS pulses to ground the 9-volt signal sent from the
engine control module (ECM) on the reference circuit.
The ECM interprets vehicle speed by the number of
pulses to ground per second on the reference circuit.
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 P0502 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the ECM battery
feed.

6E±153 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
10. To avoid backprobing the VSS and possibly
damaging a seal or terminal, the VSS output can be
tested at the point where the transmission harness
connected to the engine harness. The green 16-way
connector is adjacent to a blue 16-way connector,
and it can be easily accessed by removing the air
cleaner assembly. The green 16-way connector is
separated, and battery voltage is applied to the VSS
through the yellow wire at one corner of the
connector. The VSS output can be monitored with a
DVM connected to the blue wire with a black tracer.
The two wires are next to each other in the 16-way
connector . The test connections are made on the
transmission side of the connector, the side that is
not clipped to the body sheetmetal.11. The speedometer-to-ECM VSS signal wire is
spliced to a wire leading to the cruise control
module. If a short to ground or voltage is found
between the ECM and speedometer, it could be
located between the splice and the cruise control
module.
DTC P0502 ±VSS No Signal

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Does the speedometer work?ÐGo to Step 10Go to Step 3
31. Disconnect the VSS connector.
2. Ignition ªON.º
3. Using a test light to battery +, probe the connector
ground wire.
Did the light illuminate?
ÐGo to Step 5Go to Step 4
4Repair the sensor ground.
Is the action complete?
ÐVerify repairÐ
51. Ignition ªON,º sensor disconnected.
2. Using a DVM, measure at the VSS connector
between ground and voltage supply.
Was the measurement near the specified value?
Battery
voltage
Go to Step 7Go to Step 6
6Repair the open or short to ground which may have
blown the meter fuse.
Is the action complete?
ÐVerify repairÐ
71. Ignition ªON,º VSS disconnected.
2. Using a DVM, measure at the VSS connector
between ground and the blue/black wire from the
speedometer.
Was the measurement near the specified value?
7.5-8 VGo to Step 9Go to Step 8
8Check for an open or short circuit between the
speedometer and the VSS.
Was an open or short circuit located?
ÐVerify repairGo to Step 9
9Replace the VSS.
Is the action complete?
ÐVerify repairGo to Step 10
10Replace the speedometer.
Is the action complete?
ÐVerify repairGo to Step 11