Isuzu Trooper (1998-2002 year). Manual - part 608

6E–80

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0183 (Flash DTC 15)

 FT Sensor High Voltage

060RW129

Circuit Description

The fuel temperature (FT) sensor is a thermistor mounted
in on a coolant crossover pipe at the rear of the engine.
The Engine Control Module ECM applies a voltage (about
5 volts) through a pull-up resistor to the FT signal circuit.
When the fuel is cold, the sensor (thermistor) resistance
is high, therefore the ECM will measure a high signal
voltage.  As the fuel warms, the sensor resistance
becomes less, and the FT signal voltage measured at the
ECM drops.

Action Taken When the DTC Sets

D

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

D

DTC P0183 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the ECM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

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.

D

Damaged harness – Inspect the wiring harness for
damage.  If the harness appears to be OK, observe the
FT display on the Tech 2 while moving connectors and
wiring harnesses related to the FT sensor.  A change
in the FT display will indicate the location of the fault.

If DTC P0182 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is present.

6E–81

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0183 – FT Sensor High Voltage

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “ON,” engine “OFF.”
2. Observe the “Fuel Temp” display on the Tech 2.

Is the “Fuel Temp” below the specified value?

–39

°

C

(–38

°

F)

Go to 

Step 4

Go to 

Step 3

3

1. Ignition “ON,” engine “OFF.”
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 the “ DTC” info for DTC

P0183.

Does the Tech 2 indicate DTC P0183 failed?

—

Refer to 

Test

Description

Refer to

Diagnostic

Aids

4

1. Disconnect the FT sensor electrical connector.
2. Jumper the FT signal circuit and the sensor ground

circuit together at the FT sensor harness connector.

3. Observe the “Fuel Temp” display on the Tech 2.

Is the “Fuel Temp” at the specified value?

140

°

C

(284

°

F)

Go to 

Step 6

Go to 

Step 5

5

1. Jumper the FT signal circuit at the FT sensor

harness connector to chassis ground.

2. Observe the “Fuel Temp” display on the Tech 2.

Is the “Fuel Temp” at the specified value?

140

°

C

(284

°

F)

Go to 

Step 7

Go to 

Step 8

6

Check for poor connections at the FT sensor and
replace terminals if necessary.

Did any terminals require replacement?

—

Verify repair

Go to 

Step 10

7

1. Ignition “OFF.”
2. Disconnect the ECM, and check the FT sensor

ground circuit for an open.

3. If the FT sensor ground circuit is open, repair it as

necessary.

Was the FT sensor ground circuit open?

—

Verify repair

Go to 

Step 9

8

1. Ignition “OFF.”
2. Disconnect the ECM, and check the FT signal

circuit for an open.

3. If the FT sensor signal circuit is open, repair it as

necessary.

Was the FT signal circuit open?

—

Verify repair

Go to 

Step 9

9

Check for a poor sensor ground or FT signal circuit
terminal connection at the ECM and replace
terminal(s) if necessary.

Did any of the terminals need to be replaced?

—

Verify repair

Go to 

Step 11

10

Replace the FT sensor.

Is the action complete?

—

Verify repair

—

11

Replace the ECM (Refer to the Data Programming in
Case of ECM change).

Is the action complete?

—

Verify repair

—

6E–82

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0192 (Flash DTC 63) 

Rail Pressure Sensor Low Voltage

060RW135

Circuit Description

The rail pressure (RP) sensor responds to changes in oil
manifold pressure.
The ECM monitors the RP signals for voltages outside the
normal range of the RP sensor.  If the ECM detects a RP
signal voltage that is excessively low, DTC P0192 will be
set.

Action Taken When the DTC Sets

D

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

D

DTC P0192 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the ECM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

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.

D

Damaged harness – Inspect the wiring harness for
damage.  If the harness appears to be OK, observe the
RP 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 P0192 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 P0192 Diagnostic Chart may isolate
the cause of the fault.

6E–83

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0192 – RP Sensor Low Voltage

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “ON,” engine “OFF.”
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 “DTC” info for DTC P0192.

Does the Tech 2 indicate DTC P0192 failed?

—

Go to 

Step 3

Refer to

Diagnostic

Aids

3

Check the RP sensor signal circuit.

Was the RP sensor signal circuit open or darmage?

—

Replace the

RP circuit.

Go to 

Step 4

4

1. Ignition “OFF.”
2. Disconnect the ECM and check the 5 volt reference

“J1” circuit for an open or short to ground.

3. If the 5 volt reference “J1” circuit is open or shorted

to ground, repair it as necessary.

Was the 5 volt reference “J1” circuit open or shorted to
ground?

—

Verify repair

Go to 

Step 5

5

Check the 5 volt reference “J1” circuit for a poor
connection at the ECM and replace the terminal if
necessary.

Did the terminal require replacement?

—

Verify repair

Go to 

Step 6

6

1. Ignition “OFF.”
2. Disconnect the ECM, and check the RP signal

circuit for an open, short to ground, or short to the
sensor ground circuit.

3. If the RP sensor signal circuit is open or shorted to

ground, repair it as necessary.

Was the RP signal circuit open or shorted to ground?

—

Verify repair

Go to 

Step 7

7

Check the RP sensor signal circuit for a poor
connection at the ECM and the RP sensor; replace the
terminal if necessary.

Did the terminal require replacement?

—

Verify repair

Go to 

Step 8

8

Replace the RP sensor (Refer to the RP sensor
programming).

Is the action complete?

—

Verify repair

Go to 

Step 9

9

Replace the ECM (Refer to the Data Programming in
Case of ECM change).

Is the action complete?

—

Verify repair

—