Isuzu Trooper (2000 year). Manual - part 242

6E–97

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Reduced Power Lamp (RPL) “ON” Steady

D06RY00127

Circuit Description

The Reduced Power lamp (RPL) should always be
illuminated and steady with ignition “ON” and the engine
stopped. Ignition feed voltage is supplied directly to the
RPL indicator. The powertrain control module (PCM)
turns the 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 cased 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 PCM is

disconnected, the RPL driver wiring is not faulty.

3. If the RPL 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–98

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Reduced Power Lamp (RPL) “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 RPL (Reduced Power

Lamp).

Is the RPL “ ON?”

—

Go to 

Step 3

Go to 

Step 5

3

1. Ignition “OFF,” disconnect the instrument panel

cluster.

2. Check the RPL 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 RPL 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

RPL dash lamp control and command the RPL
“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 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 PROGRMMED
SOFTWARE to the replasement PCM.

Is the action complete?

—

Go to 

OBD

System

Check

—

6E–99

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

D06RY00150

6E–100

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

D06RY00042