Isuzu Trooper (1998-2002 year). Manual - part 488

6E–322

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

DTC P0571 No Brake Switch Signal

 

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”.

Engine “Off”.

2. Check following fuses.

D

BACK 15A

D

STOP LAMP 15A

Was a problem found?

—

Verify repair

Go to 

Step 3

3

1. Make adjustment to the brake switch.

The brake switch is installed to the brake pedal
assembly. (Refer to 

“Brake switch” in “10A CRUISE

CONTROL SYSTEM”.)

Was the problem found?

—

Verify repair

Go to 

Step 4

4

1. Push the shaft at brake switch.
2. Check shaft operation for smooth movements.

Was the problem found?

—

Verify repair

Go to 

Step 5

5

1. Disconnect the connector at brake switch.
2. Check following terminal pin at ohmmeter.

(Leave the shaft position at brake switch. Don’t
push it.)

D

Between pin 1 and pin 2

D

Between pin 3 and pin 4

Was it specified value?

Between pin1

and pin2 is

0

W

,  Between

pin3 and pin4

is 

∞

W

Go to 

Step 6

Go to 

Step 9

6

1. Disconnect the connector at brake switch.
2. Check following terminal pin at ohmmeter.

(Push the shaft position at brake switch and hold it)

D

Between pin 1 and pin 2

D

Between pin 3 and pin 4

Was it specified value?

Between pin1

and pin2 is

∞

W

,  Between

pin3 and pin4

is 0

W

Go to 

Step 7

Go to 

Step 9

7

1. Probe related circuits for open or short to ground.
2. If a problem was found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 8

8

1. Replace the ECM.

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.

Was the action completed?

—

Verify repair

—

9

1. Replace the brake switch.

Was the action completed?

—

Verify repair

—

6E–323

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0601 PCM Memory

060RY014

Circuit Description

The powertrain control module (PCM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM).  The EEPROM contains program
information and the calibrations required for engine,
transmission, and powertrain diagnostics operation.
Unlike the PROM used in past applications, the EEPROM
is not replaceable.  When the PCM is replaced or a
calibration update is required, the PCM must be
programmed using a Tech 2. Refer to 

On-Vehicle Service

in 

Powertrain Control Module and Sensors for the

EEPROM programming procedure.

Conditions for Setting the DTC

D

The PCM detects an internal program fault (check sum
error).

Action Taken When the DTC Sets

D

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

D

The PCM 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

The PCM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

D

A history DTC P0601 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P0601 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

D

DTC P0601 indicates that the contents of the
EEPROM have changed since the PCM was
programmed.  The only possible repair is PCM
replacement.  Remember to program the replacement
PCM with the correct software and calibration for the
vehicle.

6E–324

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

DTC P0601 – PCM Memory

 

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

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?

—

Verify repair

—

6E–325

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0602 PCM Programming Error

060RY014

Circuit Description

The powertrain control module (PCM) uses Main CPU
and Watchdog CPU software/calibration.

Conditions for Setting the DTC

D

This code detects inconsistencies between Main CPU
and Watchdog CPU software/calibration.

Action Taken When the DTC Sets

D

The PCM will not illuminate the malfunction indicator
lamp (MIL).

D

The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.

Conditions for Clearing the MIL/DTC

D

The PCM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

D

A history DTC P0602 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P0602 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.