Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 766

6E–88

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No Malfunction Indicator Lamp (MIL)

 

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

Attempt to start the engine.

Does the engine start?

—

Go to 

Step 3

Go to 

Step 6

3

Check the meter fuse for the instrument cluster ignition
feed circuit.

Is the fuse OK?

—

Go to 

Step 4

Go to 

Step 16

4

Ignition “ON”, probe the ignition feed circuit at the
cluster connector with a test light to ground.

Is the test light “ON”?

—

Go to 

Step 5

Go to 

Step 13

5

1. Ignition “OFF”.
2. Disconnect the PCM.
3. Jumper the MIL driver circuit at the PCM connector

to ground.

4. Ignition “ON”.

Is the MIL “ON”?

—

Go to 

Step 10

Go to 

Step 11

6

Check the PCM ignition feed and battery feed fuses (15
A engine fuse and 15 A PCM fuse).

Are both fuses OK?

—

Go to 

Step 7

Go to 

Step 15

7

1. Ignition “OFF”.
2. Disconnect the PCM.
3. Ignition “ON”.
4. Probe the ignition feed circuit at the PCM harness

connector with a test light to ground.

Is the test light “ON”?

—

Go to 

Step 8

Go to 

Step 12

8

Probe the battery feed circuit at the PCM harness
connector with a test light to ground.

Is the test light “ON”?

—

Go to 

Step 9

Go to 

Step 14

9

Check for a faulty PCM ground connection.

Was a problem found?

—

Verify repair

Go to 

Step 10

10

Check for damaged terminals at the PCM.

Was a problem found?

—

Verify repair

Go to 

Step 17

11

Check for an open MIL driver circuit between the PCM
and the MIL.

Was a problem found?

—

Verify repair

Go to 

Step 18

12

Substitute a known “good” relay for the PCM main
relay.

Was the malfunction fixed?

—

Verify repair

Go to 

Step 13

13

Repair the open in the ignition feed circuit.

Is the action complete?

—

Verify repair

—

14

Locate and repair the open PCM battery feed circuit.

Is the action complete?

—

Verify repair

—

6E–89

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No Malfunction Indicator Lamp (MIL)

  (Cont'd)

Step

No

Yes

Value(s)

Action

15

Locate and repair the short to ground in the PCM
ignition feed circuit or PCM battery feed circuit.

Is the action complete?

—

Verify repair

—

16

Locate and repair the short to ground in the ignition
feed circuit to the instrument cluster, and replace the
fuse.

Is the action complete?

—

Verify repair

—

17

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed. Refer to 

PCM in ON-Vehicle Service for

procedures.

And also refer to latest Service Bulletin.

Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.

Is the action complete?

—

Verify repair

—

18

Check the MIL driver circuit for a poor connection at the
instrument panel connector.

Was a problem found?

—

Verify repair

Go to

Instrument

Panel in

Electrical

Diagnosis

6E–90

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Malfunction Indicator Lamp (MIL) “ON” Steady

D06R200083

Circuit description

The malfunction indicator lamp (MIL) should always be
illuminated and steady with ignition “ON” and the engine
stopped.  Ignition feed voltage is supplied directly to the
MIL indicator.  The powertrain control module (PCM)
turns the MIL “ON” by grounding the MIL driver circuit.
The MIL should not remain “ON” with the engine running
and no DTC(s) set.  A steady MIL with the engine running
and no DTC(s) suggests a short to ground in the MIL
driver circuit.

Diagnostic Aids

An intermittent may be caused by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation.  Check for the following items:

D

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

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. If the MIL does not remain “ON” when the PCM is

disconnected, the MIL driver wiring is not faulty.

3. If the MIL driver circuit is OK, the instrument panel

cluster is faulty.

6. This vehicle is equipped with a PCM which utilizes

an electrically erasable programmable read only
memory (EEPROM).  When the PCM is replaced,
the new PCM must be programmed.  Refer to 

PCM

Replacement and Programming Procedures in
Powertrain Control Module (PCM) and Sensors.

6E–91

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Malfunction Indicator Lamp (MIL) “ON” Steady

 

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 “OFF”, disconnect PCM.
2. Ignition “ON”, observe the MIL (Service Engine

Soon lamp).

Is the MIL “ON”?

—

Go to 

Step 3

Go to 

Step 5

3

1. Ignition “OFF”, disconnect the instrument panel

cluster.

2. Check the MIL driver circuit between the PCM 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?

—

Go to 

OBD

System

Check

Go to 

Step 4

4

Replace the instrument panel cluster.

Is the action complete?

—

Go to 

OBD

System

Check

—

5

1. Ignition “OFF”, reconnect the PCM.
2. Ignition “ON”, reprogram the EEPROM. Refer to

On-Vehicle Service in Powertrain Control Module
and Sensors for procedures.

3. Using the Tech 2 output controls function, select

MIL dash lamp control and command the MIL
“OFF”. (Refer to the Miscellaneous test)

Did the MIL turn “OFF”?

—

Go to 

OBD

System

Check

Go to 

Step 6

6

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed. Refer to 

On-Vehicle Service in

Powertrain Control Module and Sensors for
procedures.

And also refer to latest Service Bulletin.

Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.

Is the action complete?

—

Go to 

OBD

System

Check

—