Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 351

6E–434

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1271 – APS 1– 2 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

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

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

Idle position

AP sensor 1

=13 % AP

sensor 2 =85

∼

 89 % Wide

open throttle

AP sensor 1

=85 

∼

 89 %

AP sensor 2

=11 

∼

 15 %

Refer to

Diagnostic

Aids

Go to

 Step 4

4

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

Is the AP sensor reading near the specified value?

0V

Go to

 Step 5

Go to

 Step 6 

5

1. Connect a test light between the 5 V supply circuit

and the AP sensor signal circuit at the AP1, AP2
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 8

Go to

 Step 7

6

Check the following items;

1. AP1and AP2 signal circuit for a short to voltage.
2. AP1and AP2 sensor ground circuit for high

resistance between the PCM and the AP sensor.

3. AP1and AP2 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 9 

7

Check the following items;

1. AP1and AP2 signal circuit or 5 V supply circuit for a

poor connection.

2. AP1and AP2 signal circuit or 5 V supply circuit for

high resistance between the PCM and the AP1 and
AP2 sensor.

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

necessary.

Was a problem found?

—

Verify repair

Go to

 Step 8 

6E–435

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1271 – APS 1– 2 Correlation Error

  (Cont'd)

Step

No

Yes

Value(s)

Action

8

Replace the AP sensor.

Is the action complete?

—

Verify repair

—

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

—

6E–436

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

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

060R200064

Circuit Description

D

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal sensor (AP2) will vary from
about 87 % at idle position to about 13 % at wide
open throttle (WOT) to specified voltage (about 5V).

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 more than
4.5 % between ASP2 and APS3 for more than 265
millisecond.

Action Taken When the DTC Sets

D

The PCM will not turn the malfunction indicator lamp
(MIL) “ON”.

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 P1272 will clear after 40 consecutive trip
cycles 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 connections.

D

Misrouted 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
AP sensor 2, AP 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 included in the Failure 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–437

6VE1 3.5L 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

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

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

Idleposition

AP sensor 2

=86 

∼

 88 %

AP sensor 3

=86 

∼

 88 %

Wide open

throttle    AP

sensor 2 =12

∼

 14 % AP

sensor 3 =32

∼

 36 %

Refer to

Diagnostic

Aids

Go to

 Step 4

4

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

Is the AP sensor reading near the specified value?

 0V

Go to

 Step 5

Go to

 Step 6

5

1. Connect a test light between the 5 Voltage 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 8

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 9 

7

Check the following items;

1. AP2 and AP3 signal circuit or 5 voltage supply

circuit for a poor connection.

2. AP2 and AP3 signal circuit or 5 voltage 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