2002 ISUZU AXIOM ignition

6E±428
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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
P1120 Diagnostic Chart may isolate the cause of the
fault.
DTC P1220-TPS 2 Circuit Fault

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
31. Ignition ªONº, engine not running.
2. Observe the MAP reading on the Tech 2.
Is the MAP reading less than the specified value?
65 kPaGo to Step 4Go to Step 7
41. Disconnect the MAP sensor.
2. Connect a test 5 volt reference circuit and the MAP
signal at the MAP sensor harness connector.
3. Observe the MAP reading on the Tech 2.
Is the MAP reading less than the specified value? (If no,
start with diagnosis chart for other sensors in the circuit
and see if 5V returns.)
ÐGo to Step 6Go to Step 5
51. Check the MAP signal circuit between the PCM and
MAP ground circuit.
2. If the MAP signal circuit is open or shorted, repair as
necessary.
Was the MAP signal circuit open or shorted?
ÐVerify repairGo to Step 13
6Replace the MAP sensor.
Is the action complete?
ÐVerify repairÐ
7Observe 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 TPS1
8±10 % TPS2
8±10 % WTO
TPS1 90±92
% TPS2
90±92 %
Refer to
Diagnostic
Aids
Go to Step 8
81. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech2.
Is the TP sensor reading near the specified value?
0VGo to Step 9Go to Step 10
91. Connect a test light between the 5Volt reference
circuit and the 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?
5VGo to Step 12Go to Step 11

6E±430
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnosis Trouble Code(DTC)
P1221 TPS1 ± TPS2 Correlation(Circuit Performance)
060R200069
Circuit Description

The powertrain control module (PCM) controls engine
speed by adjusting the position of the throttle control
valve (DC motor). The throttle motor is a DC motor
driven by one coil. The PCM applies current to DC
motor coil in duty (%) to adjustment the valve into a
passage in the throttle body to air flow.
This method allows highly accurate control of engine
speed and quick response to changes in engine
load.

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal angle (AP1) will vary from
about 13% at idle position to about 87% at open
throttle(WOT).
APS signal is used to determine which DC will adjust
throttle position.
After the APS signal has been processed by the
PCM, it will command the DC motor to move the
throttle position.

Accelerator pedal ± Check for objects blocking the AP
sensor or pedal arm with spring, and excessive
deposits in the accelerator pedal arm and on the
accelerator pedal.
Conditions for Setting the DTC

The ignition is ªONº.
A difference of between TPS1 and TPS2 correlation of
over 6.5% within 125 milliseconds.
Action Taken When the DTC Sets

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

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.
Condition for Clearing the MIL/DTC

A history DTC 1221 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC 1221 can be cleared using the Tech 2 ªClear Infoº
function or by disconnecting the PCM battery feed.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Visually/physically inspect for the following throttle
valve conditions.
3.Visually/physically inspect for the following
accelerator pedal conditions.
5.Check the following circuits for throttle valve and DC
moter. Check the following TP sensor resistance
and DC motor.

6E±433
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1271 APS 1± 2 Correlation Error
060R200064
Circuit Description

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal sensor (AP1) will vary from
about 13 % at idle position to about 87 % at wide
open throttle(WOT) to specified voltage (about 5V).
This code detects a correlation error between APS1
and APS2.
Conditions for setting the DTC

The Ignition is ªONº.

The accelerator pedal angle difference is more than 4.5
% between ASP1 and APS2 for more than 265
milliseconds.
Action Taken When the DTC Sets

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

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

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

A history DTC P1271 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1271 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Mis routed harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
AP sensor 1, AP sensor 2 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 P1271 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 DTCP1271 Diagnostic Chart may
isolate the cause of the fault.

6E±436
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1272 APS 2 ± 3 Correlation Error
060R200064
Circuit Description

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

The Ignition is ªONº.

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

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

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

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

A history DTC P1272 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1272 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

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±439
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1273 APS 1 ± 3 Correlation Error
060R200064
Circuit Description

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal sensor (AP1) will vary from
about 13 % at idle position to about 87 % at wide
open throttle (WOT) to specified voltage (about 5V).
This code detects a correlation error between APS1
and APS3.
Conditions for setting the DTC

The Ignition is ªONº.

The accelerator pedal angle difference is more than 4.5
% between ASP1 and APS3 for more than 265
milliseconds.
Action Taken When the DTC Sets

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

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

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

A history DTC P1273 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1273 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
AP sensor 1, 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 P1273 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
P1273 Diagnostic Chart may isolate the cause of the
fault.

6E±442
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1275 APS 1 Output Fault
060R200064
Circuit Description

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal sensor (AP1) will vary from
about 13 % at idle position to about 87 % at wide
open throttle (WOT) to specified voltage (about 5V).
This code detects a continuous short to ground or
high in either the circuit or the sensor.
Conditions for setting the DTC

The Ignition is ªONº.

The accelerator pedal sensor 1 is less than 2.5 % or
more than 97 % in the specified voltage (5V) for more
than 62.4 milliseconds.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected fault.

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

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

A history DTC P1275 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1275 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
APP sensor 1 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 P1275 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
P1275 Diagnostic Chart may isolate the cause of the
fault.

6E±444
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1280 APS 2 Output Fault
060R200064
Circuit Description

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 continuous short to ground or
high in either the circuit or the sensor.
Conditions for setting the DTC

The Ignition is ªONº.

The accelerator pedal sensor 2 is less than 2.5 % or
more than 97 % in the specified voltage (5V) for more
than 62.4 milliseconds.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected fault.

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

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

A history DTC P1280 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1280 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
APP sensor 2 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 P1280 cannot be duplicated, the
information included in the Failure Records data can
be useful in determining vehicle mileage since the
DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC
P1280 Diagnostic Chart may isolate the cause of the
fault.

6E±446
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1285 APS 3 Output Fault
060R200064
Circuit Description

The accelerator position (AP) sensor circuit provides a
voltage signal relative to accelerator pedal angle.
The accelerator pedal sensor (AP3) will vary from
about 87 % at idle position to about 34 % at wide
open throttle(WOT) to specified voltage (about 5V).
This code detects a continuous short to ground or
high in either the circuit or the sensor.
Conditions for setting the DTC

The Ignition is ªONº.

The accelerator pedal sensor 3 is less than 2.5 % or
more than 97 % in the specified voltage (5V) for more
than 62.4 milliseconds.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.

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

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

A history DTC P1285 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1285 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

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.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
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 P1285 cannot be duplicated, the
information included in the Failure Records data can
be useful in determining vehicle mileage since the
DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC
P1285 Diagnostic Chart may isolate the cause of the
fault.