ISUZU AXIOM 2002 Service Repair Manual

6E±464
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1311 - ION Sensing Module SEC Line 1 Circuit Fault

 
StepNo Ye s Value(s) Action
10Replace the ION Sensing module.
Is the action complete?
ÐVerify repairGo to Step 11
11Replace 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±465
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1312 ION Sensing Module SEC Line 2 Circuit Fault
060R200068
Circuit Description

The Power Control Module (PCM) will compare the
secondary current reading to predetermined maximum
and minimum thresholds.
If the secondary current signal pulse width is out of
the predetermined range, the fail counter will be
incremented. If the fail counter exceeds the
calibration, then the PCM is complete and a failure
will be reported. If the sample counter threshold is
reached before the failure threshold, then the PCM is
complete and pass will be reported.
This PCM will detect an open/short circuit in the
secondary current sense input circuit, misfire on the
entire bank for the secondary current sense input
circuit, coil failure, and same internal Ignition Current
Sense System (ICSS) module faults.
Conditions for setting the DTC

Ignition voltage is between 10volt and 16 volts.

MAP sensor signal is between 26kPa and 100 kPa.

Fuel level is more than 19%.

Engine speed is between 650rpm and 6500rpm.

ION Sensing Module circuit is open or shorted signals
on the SEC 2 line.
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 idle air
control valve position, throttle 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 P1312 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1312 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:

6E±466
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

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
moving connectors and wiring harnesses related to the
sensor.A change in the display will indicate the location of
the fault. If DTC P1312 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 P1312 Diagnostic Chart may
isolate the cause of the fault.
DTC P1312 - ION Sensing Module SEC Line 2 Circuit Fault

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. 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 P1312.
Does the Tech 2 indicate DTC P1312 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Ignition ªOFFº.
2. Disconnect the ION Sensing module.
3. Disconnect the PCM.
Is the action complete?
ÐGo to Step 4Go to Step 3
4Check the ION Sensing module harness between the
PCM and ICSS module circuit at the ION Sensing
Module harness connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Disconnect the ignition coil.
Is the action complete?
ÐGo to Step 6Go to Step 5
6Check the ION Sensing module harness between the
ignition coil and ION Sensing module circuit at the SEC
line 2 harness connector.
Was a problem found?
ÐVerify repairGo to Step 7
7Check the following items;
1. Ignition coil and ignition coil circuit.
2. Ignition coil ground circuit for a poor connection.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8
8Replace the Ignition coil.
Is the action complete?
ÐVerify repairGo to Step 9
9Check the following items;
1. ION Sensing module ground circuit for a poor
connection.
2. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 10

6E±467
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1312 - ION Sensing Module SEC Line 2 Circuit Fault

 
StepNo Ye s Value(s) Action
10Replace the ION Sensing module.
Is the action complete?
ÐVerify repairGo to Step 11
11Replace 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±468
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1326 ION Sensing Module Combustion Quality Input Circuit Fault
060R200068
Circuit Description
The Power Control Module (PCM) checks the validity of
the signals used in the ION Sensing module at the
following engine operating conditions.

The test is performed to evacuate the Combustion
Quality (CQ) signal pulse width if it is within a
predetermined range. If the CQ signal pulse width is
out of the predetermined range, the fail counter will be
incremented. If the failure counter exceeds the
calibration, then test is complete and a failure will be
reported. If the sample counter threshold is reached
before the failure threshold, then the test is complete
and a pass will be reported. This test will detect an
open/short in the CQ line circuit, ION Sensing module
faults and analog input faults in the PCM.
Conditions for setting the DTC

Ignition voltage is between 10volt and 16 volts.

No Crank DTCs set.

No cylinder ID DTCs set.
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 idle air
control valve position, throttle 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 P1326 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1326 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
moving connectors and wiring harnesses related to the
sensor.
A change in the display will indicate the location of
the fault. If DTC P1326 cannot be duplicated, the
information included in the Failure Records data can

6E±469
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
be useful in determined vehicle mileage since the
DTC was last set.If it is determined that the DTC occurs intermittently,
performing the DTC P1326 Diagnostic Chart may
isolate the cause of the fault.
DTC P1326 - ION Sensing Module Combustion

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. 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 P1326.
Does the Tech 2 indicate DTC P1326 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Ignition ªOFFº.
2. Disconnect the ION Sensing module.
3. Disconnect the PCM.
Is the action complete?
ÐGo to Step 4Go to Step 3
4Check the ION Sensing module harness between the
PCM and ION Sensing module circuit at the QC line
harness connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Disconnect the ignition coil.
Is the action complete?
ÐGo to Step 6Go to Step 5
6Check the ION Sensing module harness between the
ignition coil and ICSS module circuit at the ION Sensing
Module harness connector.
Was a problem found?
ÐVerify repairGo to Step 7
7Check the following items;
1. Ignition coil and ignition coil circuit.
2. Ignition coil ground circuit for a poor connection.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8
8Replace the Ignition coil.
Is the action complete?
ÐVerify repairGo to Step 9
9Check the following items;
1. ION Sensing module ground circuit for a poor
connection.
2. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 10

6E±470
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1326 - ION Sensing Module Combustion

 
StepNo Ye s Value(s) Action
10Replace the ION Sensing module.
Is the action complete?
ÐVerify repairGo to Step 11
11Replace 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±471
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1340 ION Sensing Module Cylinder ID Fault (Cylinder Synchronization Fail)
060R200068
Circuit Description
The Power Control Module (PCM) checks the validity of
the signals used in the ION Sensing module at the
following engine operating conditions.

This test will return a fault if the cylinder
synchronization routine has not been completed after
a predetermined number of events after crank. This
test will detect fault that will prevent the PCM from
synchronization, such as Knock Signal (KI) -
Combustion Quality (CQ) lines being swapped,
shorted spark plugs, ION Sensing module faults, an
PCM hardware faults.
Conditions for setting the DTC

Ignition voltage is between 11volts and 16 volts.

Engine speed is between 650rpm and 6250rpm.

No ECT DTCs set.

No injector DTCs set.

No Fuel Trim DTCs set.

No Misfire DTCs set.

No system voltage DTCs set.
Action Taken When the DTC Sets

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

The PCM calculates an air flow value based on idle air
control valve position, throttle 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 P1340 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1340 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
moving connectors and wiring harnesses related to the
sensor.

6E±472
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A change in the display will indicate the location of
the fault. If DTC P1340 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 P1340 Diagnostic Chart may
isolate the cause of the fault.
DTC P1340 - ION Sensing Module Cylinder ID Fault
(Cylinder Synchronization Fail)

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. 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 ª DTCº info for DTC P1340.
Does the Tech 2 indicate DTC P1340 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Ignition ªOFFº.
2. Disconnect the ION Sensing module.
3. Disconnect the PCM.
Is the action complete?
ÐGo to Step 4Go to Step 3
4Check the ION Sensing module harness between the
PCM and ICSS module circuit at the QC line harness
connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Disconnect the ignition coil.
Is the action complete?
ÐGo to Step 6Go to Step 5
6Check the ION Sensing module harness between the
ignition coil and ION Sensing module circuit at the ION
Sensing Module harness connector.
Was a problem found?
ÐVerify repairGo to Step 7
7Check the following items;
1. Ignition coil and ignition coil circuit.
2. Ignition coil ground circuit for a poor connection.
3. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 8
8Replace the Ignition coil.
Is the action complete?
ÐVerify repairGo to Step 9
9Check the following items;
1. ION Sensing module ground circuit for a poor
connection.
2. If a problem is found, repair wiring harness as
necessary.
Was a problem found?
ÐVerify repairGo to Step 10

6E±473
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1340 - ION Sensing Module Cylinder ID Fault
(Cylinder Synchronization Fail)

 
StepNo Ye s Value(s) Action
10Replace the ION Sensing module.
Is the action complete?
ÐVerify repairGo to Step 11
11Replace 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