Isuzu Trooper (2000 year). Manual - part 338

6E–481

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1523 - Actuator Control Return Performance

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board (OBD) System Check” performed?

—

Go to

 Step 2

Go to

 OBD

System

Check

2

Was the “Electric Throttle Control (ETC) System
Check” performed?

—

Go to 

Step 3

Go to 

ETC

System

Check

3

Observe the TP angle reading on the Tech 2 while
slowly opening the throttle.

Does the TP angle increase steadily and evenly from
the closed throttle value to the wide open  throttle
value?

Closed

throttle    TP

sensor 1 =8 

∼

10 % TP

sensor 2 =90

∼

 92 % Wide

open throttle

 TP sensor 1

=90 

∼

 92 %

TP sensor 2

=8 

∼

 10 %

Go to

 Step 7

Go to

 Step 4

4

1. Ignition “OFF.”
2. Disconnect the DC motor.

Is the DC motor reading near the specified value?

0.3 

∼

 100 

m

Go to

 Step 5

Go to

 Step 6

5

Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.

Was a problem found?

—

Verify repair

Go to

 Step 7

6

Replace the DC motor.

Is the action complete?

—

Verify repair

Go to

 Step 5

7

1. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.

Is the TP sensor reading near the specified value?

0V

Go to

 Step 8

Go to

 Step 9

8

1. Connect a test light between the 5Volt reference

circuit and the TP1 and TP2 sensor signal circuit at
the TP sensor harness connector.

2. Observe the TP sensor reading on the Tech 2.

Is the TP sensor reading near the specified value?

5V

Go to

 Step 11

Go to

 Step 10

9

Check the following items;

1. TP1 and TP2 signal circuit for a short to voltage.
2. TP1 and TP2 sensor ground circuit for high

resistance between the PCM and the TP sensor.

3. TP1and TP2 sensor ground circuit for a poor

connection.

4. If a problem is found, repair wiring harness as

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 12

6E–482

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1523 - Actuator Control Return Performance

  (Cont'd)

Step

No

Yes

Value(s)

Action

10

Check the following items;

1. TP1and TP2 signal circuit or 5 volt reference circuit

for a poor connection.

2. TP1 and TP2 signal circuit or 5 volt reference circuit

for high resistance between the PCM and the
TP1and TP2 sensor.

3. If a problem is found, repair wiring harness as

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 12

11

Replace the TP sensor.

Is the action complete?

—

Verify repair

—

12

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 replasement PCM.

Is the action complete?

—

Verify repair

—

6E–483

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P1625 PCM Unexpected Reset

Circuit Description

The powertrain control module (PCM) monitors
unexpected PCM reset. This will not turn on MIL light on,
only records code DTC P1625.

Conditions for Setting the DTC

D

Clock or COP (Computer Operating Properly) reset.

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 as Failure Records only. This
information will not be stored as Freeze Frame 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 P1625 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P1625 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

P1625 alone stored does not need diagnosis. Clear
DTC code.

DTC P1625 – PCM Unexpected Reset

 

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 is “ON”.
2. Install the Tech 2.
3. Start the engine at let it Idle.
4. On the Tech 2, select “DTC info”.

Does the Tech 2 indicate DTC P1625 failed?

—

Go to 

Step 3

Go to

Diagnostic

Aids

3

1. Ignition is “ON”.
2. Clear DTC P1625 by using the Tech 2 “Clear Info”.
3. Start the engine at let it Idle.
4. On the Tech 2, select “DTC info”.

Does the Tech 2 indicate DTC P1625 failed?

—

Go to 

Step 4

Go to

Diagnostic

Aids

4

1. Check for aftermarket electronics, such as

transceiver, stereos, and anti theft devices. They
may radiate EMI into the control system if they are
improperly installed. (This may cause a false sensor
reading and turn on the MIL.)

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

—

6E–484

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P1635 Reference Voltage # 1 Circuit Fault

D06RY00077

Circuit Description

The TP sensor # 1 shares a 5 Volt reference with the
PCM.
If the PCM detects the 5 Volt reference for the TP sensor #
1 is failure, DTCP1635 will be set.

Conditions for setting the DTC

D

The ignition is “ON”.

D

The 5 Volt reference voltage for the TP sensor # 1 is
less than 4 volts.

D

The 5 Volt reference voltage for the TP sensor # 1 is
more than 5 volts.

Action Taken When the DTC Sets

D

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

D

The PCM will store condition 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 condtion is no longer present.

D

A history DTC P1635will clear after 40 cosecutive trip
cycle during which the warm up cycles have occurred
without a fault.

D

DTC P1635 can be cleared using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed. Tech2 “ Clear Info” function or by disconnecting
the PCM battery feed.