Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 265

6E–90

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No Reduced Power Lamp (RPL)

 

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 11

3

Check the following fuses:
MAIN(100A), B+1(60A), B+2(50A), METER(15A),
ECM(15A) , ENGINE(15A)

Was a problem found?

—

Go to 

Step 14

Go to 

Step 4

4

1. Ignition ”OFF”.
2. Disconnect the cluster meter connector.
3. 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 15

5

1. Ignition “OFF”.
2. Disconnect the Multiplex Control Unit.
3. Check the circuit (Lamp driver Circuit) between

PCM and Multiplex Control Unit.

Was a problem found?

—

Go to 

Step 16

Go to 

Step 6

6

1. Reconnect the cluster meter connector.
2. Disconnect the Multiplex Control Unit.
3. Jumper the RPL driver circuit at the Multiplex

Control Unit connector to ground.

4. Ignition “ON”.

Is the RPL “ON”?

—

Go to 

Step 7

Go to

Instrument

Panel in

Electrical

Diagnosis

7

1. Ignition “OFF”.
2. Probe the ignition feed circuit at the Multiplex

Control Unit connector with a test light to ground.

3. Ignition “ON”.

Is the test light “ON”?

—

Go to 

Step 8

Go to 

Step 17

8

1. Ignition “OFF”.
2. Disconnect the PCM.
3. Check the circuit (Lamp driver Circuit) between

PCM and Multiplex Control Unit.

Was a problem found?

—

Go to 

Step 18

Go to 

Step 9

9

Check the Multiplex Control Unit ground connection
and circuit.

Was a problem found?

—

Go to 

Step 19

Go to 

Step 10

10

Check for damaged terminals at the Multiplex Control
Unit.

Was a problem found?

—

Go to 

Step 20

Go to 

Step 11

11

1. Ignition “ON”.
2. Probe the ignition feed circuit at the PCM harness

connector with a test light to ground.

Is the test light “ON”?

—

Go to 

Step 12

Go to 

Step 21

6E–91

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No Reduced Power Lamp (RPL)

  (Cont'd)

Step

No

Yes

Value(s)

Action

12

1. Ignition “OFF”.
2. Check for a faulty PCM ground connection and

Circuit.

Was a problem found?

—

Go to 

Step 23

Go to 

Step 13

13

Check for damaged terminals at the PCM.

Was a problem found?

—

Go to 

Step 24

Go to 

Step 25

14

Replace the fuse.

Is the action complete?

—

Verify repair

—

15

Locate and repair the cluster meter battery feed open
circuit.

Is the action complete?

—

Verify repair

—

16

Locate and repair the circuit between cluster meter and
Multiplex Control Unit open circuit.

Is the action complete?

—

Verify repair

—

17

Locate and repair the circuit Multiplex Control Unit
battery feed open circuit.

Is the action complete?

—

Verify repair

—

18

Locate and repair the between Multiplex Control Unit
and PCM open circuit.

Is the action complete?

—

Verify repair

—

19

Locate and repair the ground connection for Multiplex
Control Unit circuit.

Is the action complete?

—

Verify repair

—

20

Reconnect the Multiplex Control Unit. circuit.

Is the action complete?

—

Verify repair

—

21

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

Was the malfunction fixed?

—

Verify repair

Go to 

Step 22

22

Repair the open in the ignition feed circuit.

Is the action complete?

—

Verify repair

—

23

Locate and repair the ground connection for PCM
circuit.

Is the action complete?

—

Verify repair

—

24

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed.

Refer to ON-Vehicle Service in Power 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?

—

Verify repair

—

6E–92

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

No Reduced Power Lamp (RPL)

  (Cont'd)

Step

No

Yes

Value(s)

Action

25

1. Ignition “OFF”.
2. Reconnect all connectors.
3. Install the Tech 2.
4. Ignition “ON”.
5. Using the Tech 2 output controls function, select

RPL dash lamp control and command the RPL
“ON”. (Refer to the Miscellaneous test)

Did the RPL turn “ON”?

—

Verify repair

Go to 

Step 26

26

1. Ignition “OFF”.
2. Disconnect the PCM.
3. Check the circuit (DLC line) between PCM and

DLC.

Was a problem found?

—

Go to 

Step 27

Go to 

Step 24

27

Locate and repair the circuit the between PCM and
DLC.

Is the action complete?

—

Go to 

Step 25

—

6E–93

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Reduced Power Lamp (RPL) “ON” Steady

060R200073

Circuit Description

The Reduced Power lamp (RPL) should always be
illuminated and steady with the ignition “ON” and the
engine stopped. Ignition feed voltage is supplied to the
RPL bulb through the meter fuse. The powertrain control
module (PCM) orders the RPL “ON” signal for Multiplex
Control Unit. When Multiplex Control Unit is received RPL
“ON” signal that turn RPL “ON” by grounding the RPL
driver circuit.
The RPL should not remain “ON” with the engine running
and no DTC(s) set. A steady RPL with the engine running
and no DTC(s) suggests a short to ground in the RPL
driver circuit.

Diagnostic Aids

An intermittent RPL 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 RPL does not remain “ON” when the Multiplex

Control Unit is disconnected, the RPL driver wiring
is not faulty.

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

cluster is faulty.

10. 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.