Isuzu Trooper (1998-2002 year). Service manual - part 623

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

D

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

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 P0475 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.

6E–141

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P0475 – EXH #1 VSV Circuit Open/Short

 

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.”  Review and record

Tech 2 Failure Records data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor the “ DTC” info for DTC

P0475.

Does the Tech 2 indicate DTC P0475 failed this
ignition?

—

Go to 

Step 3

Refer to

Diagnostic

Aids

3

1. Ignition “OFF.”
2. Disconnect the EXH #1 VSV connectors.
3. Check the EXH #1 VSV circuit for a short to ground.

Is the EXH #1 VSV circuit shorted to ground?

—

Verify repair

Go to 

Step 4

4

Replace the EXH #1 VSV.

Is the action complete?

—

Verify repair

Go to 

Step 5

5

1. Ignition “ON,” engine “OFF.”  Review and record

Tech 2 Failure Records data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor the “ DTC” info for DTC

P0475.

Does the Tech 2 indicate DTC P0475 failed this
ignition?

—

Go to 

Step 6

—

6

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

Is the action complete?

—

Verify repair

—

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

D

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

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 P1475 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.

6E–143

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

DTC P1475 – EXH #2 VSV Circuit Open/Short

 

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.”  Review and record

Tech 2 Failure Records data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor the “ DTC” info for DTC

P1475.

Does the Tech 2 indicate DTC P1475 failed this
ignition?

—

Go to 

Step 3

Refer to

Diagnostic

Aids

3

1. Ignition “OFF.”
2. Disconnect the EXH #2 connectors.
3. Check the EXH #2 circuit for a short to ground.

Is the EXH #2 circuit shorted to ground?

—

Verify repair

Go to 

Step 4

4

Replace the EXH #2 VSV.

Is the action complete?

—

Verify repair

Go to 

Step 5

5

1. Ignition “ON,” engine “OFF.”  Review and record

Tech 2 Failure Records data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor the “ DTC” info for DTC

P1475.

Does the Tech 2 indicate DTC P1475 failed this
ignition?

—

Go to 

Step 6

—

6

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

Is the action complete?

—

Verify repair

—