Isuzu Trooper (1998-2002 year). Manual - part 504

6E–386

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

DTC P1271 – APS 1– 2 Correlation Error

  (Cont'd)

Step

No

Yes

Value(s)

Action

8

Replace the AP sensor.

Was a problem corrected?

—

Verify repair

Go to

 Step 9

9

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 ornot. And then Down
Load the LATEST PROGRAMMED SOFTWARE to the
replasement PCM.

Is the action complete?

—

Verify repair

—

6E–387

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P1272 APS 2 – 3 Correlation Error

D06RY00075

Circuit Description

D

The acceleration position (AP) sensor circuit provides
a voltage signal relative to acceleration pedal angle.
The acceleration pedal angle (AP2) will vary about
87 % at idle position to about 13 % at wide open
throttle (WOT).

This code detects a correlation error betweenAPS2
and APS3.

Conditions for setting the DTC

D

The Ignition is “ON”.

D

The acceleration pedal angle difference is less than 4.5
% between ASP2 and APS3 for 50 counts within 50
test samples (15.6 m sec).

Action Taken When the DTC Sets

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 condition is no longer present.

D

A history DTC P1272 will clear after 40 consecutive trip
cycle during which the warm up cycles have occurred
without a fault.

D

DTC P1272 can be cleared using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

An intermittent may be caused by the following:

D

Poor connectons.

D

Mis routed harness.

D

Rubbed through wire insulation.

D

Broken wire inside the insulation.

Check for the following conditions:

D

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

D

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
APP sensor 2, APP sensor 3 display on the Tech 2
while moving connectors and wiring harnesses related
to the sensor.
A change in the display will indicate the location of
the fault. If DTC P1272 cannot be duplicated, the
information includedin the Faillure Records data can
be useful in determined vehicle mileage since the
DTC was last set.

If it is determined that the DTC occurs intermittently,
performing the DTC

P1272 Diagnostic Chart may isolate the cause of the
fault.

6E–388

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

DTC P1272 – APS 2 – 3 Correlation Error

 

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

1. Warming up the engine until the ECT rise at 80

°

C

2. Ignition “OFF”.
3. Ignition  ON” but not engine run.
4. Observe the AP angle reading on the Tech 2 while

alowly opening the throttle.

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

Closed

throttle APS2

= 85

∼

89%

APS3 =

85

∼

89% Wide

open throttle

APS2 =

11

∼

15%

APS3 =

32

∼

36%

Go to

 Step 4

Go to

 Step 5

4

Was the DTC P1272 stored?

—

Go to

 Step 9

Check the

procedure.Re

fer to

Diagnositc

Aids

5

1. Connect a test light between the 5 Voltge supply

circuit and the AP sensor signal circuit at the AP2
and AP3 sensor harness connector.

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

Is the AP sensor reading near the specified value?

5V

Go to

 Step 6

Go to

 Step 7

6

Check the following items;

1. AP2 and AP3 signal circuit for a short to voltage.
2. AP2 and AP3 sensor ground circuit for high

resistance between the PCM and the AP sensor.

3. AP2 and AP3 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 7 

7

Check the following items;

1. AP2 and AP3 signal circuit or 5 volge supply circuit

for a poor connection.

2. AP2 and AP3 signal circuit or 5 volge supply circuit

for high resistance between the PCM and the AP2
and AP3 sensor.

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

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 8 

6E–389

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1272 – APS 2 – 3 Correlation Error

  (Cont'd)

Step

No

Yes

Value(s)

Action

8

Replace the AP sensor.

Was a probelm corrected?

—

Verify repair

Go to

 Step 9

9

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

—