ISUZU AXIOM 2002 Service Repair Manual

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±445
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1280 - APS 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
3Observe 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
=86 ~ 88
%Wide open
throttle =12
~ 14 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 voltage supply
circuit and the AP2 sensor signal circuit at the AP
sensor harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP2 signal circuit for a short to volt.
2. AP2 sensor ground circuit for high resistance
between the PCM and the AP sensor.
3. AP2 sensor ground circuit for a poor connection.
4. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
7Check the following items;
1. AP2 signal circuit or 5 volt supply circuit for a poor
connection.
2. AP2 signal circuit or 5 volt supply circuit for high
resistance between the PCM and the AP2 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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?
ÐVerify repairÐ

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.

6E±447
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1285 ± APS 3 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
3Observe 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
=86 ~ 88
%Wide open
throttle =32
~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 volt supply circuit
and the AP3 sensor signal circuit at the AP sensor
harness connector.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP3 signal circuit for a short to voltage.
2. AP3 sensor ground circuit for high resistance
between the PCM and the AP sensor.
3. AP3 sensor ground circuit for a poor connection.
4. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
7Check the following items;
1. AP3 signal circuit or 5 volt supply circuit for a poor
connection.
2. AP3 signal circuit or 5 voltage supply circuit for high
resistance between the PCM and the AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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?
ÐVerify repairÐ

6E±448
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1290 ETC Forced Idle Mode
060R200069
Circuit Description

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 wide
open throttle (WOT).
This code detects that if the system is in Forced Idle
Mode. (Fail safe Mode)
Conditions for setting the DTC

The Ignition is ªONº.

Forced Idle Mode is active. (Fail safe Mode)
Action Taken When the DTC Sets

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

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 P1290 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P1290 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, 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 P1290 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
P1290 Diagnostic Chart may isolate the cause of the
fault.

6E±449
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1290 - ETC Forced Idle Mode

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
3Observe the AP angle reading on the Tech2 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
=12 ~ 14 %
AP sensor 2,
3 =86 ~ 88 %
Wide open
throttle AP
sensor 1 =86
~ 88 % AP
sensor 2 =12
~ 14 % AP
sensor 3 =32
~ 36 %
Refer to
Diagnostic
Aids
Go to Step 4
41. Disconnect the AP sensor.
2. Observe the AP sensor reading on the Tech 2.
Is the AP sensor reading near the specified value?
0VGo to Step 5Go to Step 6
51. Connect a test light between the 5 voltage supply
circuit and the AP1, AP2 and AP3 sensor signal
circuit at the AP sensor harness connector.
2. Observe the AP sensor reading on the Tech2.
Is the AP sensor reading near the specified value?
5VGo to Step 8Go to Step 7
6Check the following items;
1. AP1,AP2 and AP3 signal circuit for a short to
voltage.
2. AP1, AP2 and AP3 sensor ground circuit for high
resistance between the PCM and the AP sensor.
3. AP1, 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?
ÐVerify repairGo to Step 9
7Check the following items;
1. AP1, AP2 and AP3 signal circuit or 5 volt supply
circuit for a poor connection.
2. AP1, AP2 and AP3 signal circuit or 5 volt supply
circuit for high resistance between the PCM and the
AP1, AP2 and AP3 sensor.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 9

6E±450
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1290 - ETC Forced Idle Mode

 
StepNo Ye s Value(s) Action
8Replace the AP sensor.
Is the action complete?
ÐVerify repairÐ
9Replace 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?
ÐVerify repairÐ

6E±451
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1295 ETC Power Management Mode
D06RY00111
Circuit Description

The throttle position (TP) sensor circuit provides a
voltage signal relative to throttle position (blade angle).
The throttle blade angle will vary from about 8 % at
closed throttle to about 92 % at wide open throttle
(WOT).

The DC motor circuit provides a voltage signal relative
to command throttle position (blade angle).

The mass air flow (MAF) sensor measures the amount
of air which passes through it into the engine during a
given time. The powertrain Control Module (PCM)
uses the mass air flow information to monitor engine
operating conditions for fuel delivery calculations.
A large quantity of air entering the engine indicates
an accelerator or high load situation, while a small
quantity or air indicates deceleration or idle.
The MAF sensor produces a frequency signal which
can be monitored using a Tech 2. The frequency will
vary within a range of around 4 to 7g/s at idle to
around 25 to 40g/s at maximum engine load.

This DTC detects that if the system is in Power
Management Mode.(Fail safe Mode)
Conditions for setting the DTC

The ignition is ªONº.

Power Management Mode is active. (Fail safe Mode)
Action Taken When the DTC Sets

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

The PCM calculates an air flow value based on throttle
blade position, RPM and barometric pressure.

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 P1295 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1295 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

6E±452
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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
TP sensor 1, TP 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 P1295 cannot be duplicated, theinformation included in the Failure Records data can
be useful in determined vehicle mileage since the
DTC was last set.
If it is determining that the DTC occurs intermittently,
performing the DTC
P1295 Diagnostic Chart may isolate the cause of the
fault.
DTC P1295 - ETC Power Management Mode

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 ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor ªDTCº info for DTC P1295.
Does the Tech 2 indicate DTC P1295 failed this
ignition?
ÐGo to Step 4
Refer to
Diagnostic
Aids
4Observe 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 9Go to Step 5
51. Ignition ªOFFº.
2. Disconnect the DC motor.
Is the DC motor reading near the specified value?
0.3 ~ 100
Go to Step 6Go to Step 8
6Check the DC motor harness between the PCM and
DC Motor circuit at the DC motor harness connector.
Was a problem found?
ÐVerify repairGo to Step 7
7Check the throttle valve assembly.
Was a problem found?
Verify repairGo to Step 8
8Replace the DC motor. (Replace the Throttle valve
assembly)
Is the action complete?
ÐVerify repairÐ
91. Disconnect the TP sensor.
2. Observe the TP sensor reading on the Tech 2.
Is the TP sensor reading near the specified value?
0VGo to Step 10Go to Step 11

6E±453
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1295 - ETC Power Management Mode

 
StepNo Ye s Value(s) Action
101. Connect a test light between the 5Volt reference ªAº
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?
5VGo to Step 13Go to Step 12
11Check 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?
ÐVerify repairGo to Step 14
12Check 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?
ÐVerify repairGo to Step 14
13Replace the TP sensor.
Is the action complete?
ÐVerify repairÐ
141. Start the engine.
2. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
Is the ªMAF Frequencyº below the specified value?
6 ~ 10 g/sGo to Step 15Go to Step 18
151. Ignition ªOFFº.
2. Disconnect the MAF sensor connector.
3. Ignition ªONº, engine idling.
4. Using a Tech 2, monitor ªMAF Frequencyº.
Does the Tech 2 indicate a ªMAF Frequencyº at the
specified value?
0g/sGo to Step 16Go to Step 17
16Replace the MAF sensor.
Is the action complete?
ÐVerify repairÐ
171. Check the MAF harness for incorrect routing near
high voltage components (solenoids, relays,
motors).
2. If incorrect routing is found, correct the harness
routing.
Was a problem found?
ÐVerify repairGo to Step 23
181. With the engine idling, monitor ªMAF Frequencyº
display on the Tech 2.
2. Quickly snap open throttle to wide open throttle
while under a road load and record value.
Does the Tech 2 indicate a ªMAF Frequencyº at the
specified value?
6 ~ 10 g/sGo to Step 16Go to Step 19