2002 ISUZU AXIOM air condition

6E±270
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0306 Cylinder Misfire Detected
Circuit Description
Misfire is monitored as a function of the combustion
quality (CQ) signals generated from the ignition current
sense system. Combustion signals represent the degree
of combustion in each cylinder. Misfire is detected when
the combustion signal is below a predetermined value.
This DTC P0306 will determine if the No.6 cylinder misfire
is occurring by monitoring the Combustion Quality.
Conditions for Setting the DTC

None of the following occur: TP sensor, MAF sensor,
vehicle speed sensor, ECT sensor.

The engine speed is between 600 and 6250 RPM.

The system voltage is between 11 and 16 volts.

The ECT indicates an engine temperature between
±7
C (28
F) and 110
C (230
F).

The throttle angle is steady and throttle change less
than 2% per 125 milliseconds.
Action Taken When the DTC Sets

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

If the misfire is severe enough to cause possible
catalyst damage, the PCM will flash the MIL for as long
as the misfire remains at catalyst damaging levels.

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 ignition cycle in which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P0306 will clear after 40 consecutive
ignition cycles occur without a fault.

DTC P0306 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:

System grounds ± Ensure all connections are clean
and properly tightened.

Injector ± Perform the injector coil/balance test to
locate a faulty injector that contributes to a lean
condition on the affected cylinder. In addition to the
above test, check the condition of the injector O-ring.

Faulty spark plug ± Check for a cracked insulator,
carbon tracking, incorrect gap, and worn electrodes.

Damaged or faulty ignition coil ± Check for cracks or
other damage.

Substitute a known good coil ± Swap the ignition coils
and retest. If the misfire follows the coil, replace the
ignition coil.
DTC P0306 ± Cylinder Misfire Detected

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Start the engine. Run the engine at idle.
2. Review and record Tech 2 Freeze Frame data.
3. Monitor ªMisfire Cur. #6º on the Tech 2.
Is ªMisfire Cur. #6º increasing (indicating a misfire
currently occurring)?
ÐGo to Step 4Go to Step 3
3Monitor ªMisfire Hist. #6º while operating the vehicle to
duplicate the conditions present when the DTC was set
(as defined by the Freeze Frame data recorded in Step
2).
Is ªMisfire Hist. #6º increasing (indicating a misfire
currently occurring)?
ÐGo to Step 4
Refer to
Diagnostic
Aids
41. Visually and physically inspect the vacuum hoses
for splits, kinks, and improper connections. Also,
inspect the intake manifold for a vacuum leak.
2. If a problem is found, repair it as necessary.
Did the inspection reveal a problem?
ÐVerify repairGo to Step 5
51. Install a spark tester at the spark plug end of the
cylinder #6 ignition wire.
2. Crank the engine while observing the spark tester.
A crisp, blue spark should be observed.
Is adequate spark present?
ÐGo to Step 8Go to Step 6

6E±271
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0306 ± Cylinder Misfire Detected

 
StepNo Ye s Value(s) Action
61. Remove and visually/physically inspect the ignition
coil associated with cylinder #6. Ensure that the coil
is free of cracks and carbon tracking.
2. If a problem is found, replace the damaged ignition
coil as necessary.
Did the visual inspection reveal a problem?
ÐVerify repairGo to Step 7
71. Measure the ignition coil primary resistance.
2. If resistance is not within the specified value,
replace the faulty ignition coil.
Did the ignition coil require replacement?
2.6-2.7 K
Verify repair Go to Step 12
8Remove the cylinder #6 spark plug and visually inspect
the spark plug electrode.
Does the inspection reveal excessive fouling?
Ð
Go to
Contaminatio
n Diagnosis
chart in
Engine
Mechanical
Diagnosis
Go to Step 9
91. Visually inspect the spark plug insulator for cracks,
carbon tracking, or other damage.
2. If the spark plug is damaged, replace the spark plug.
Did the inspection reveal a problem?
ÐVerify repairGo to Step 10
101. Perform the ªInjector Coil/Balance Testº.
2. If any faulty injectors are found, replace them as
necessary.
Did any of the injectors require replacement?
ÐVerify repairGo to Step 11
111. Inspect the intake manifold and the injector O-rings
for a vacuum leak.
2. If a problem is found, repair it as necessary.
Did the inspection reveal a problem?
ÐVerify repairGo to Step 12
12Check for an engine mechanical problem. Refer to
Engine Mechanical Diagnosis to diagnose and repair
the following conditions:

A faulty or incorrect camshaft

Leaking or sticky valves or rings

Excessive valve deposits

Weak valve springs

A leaking head gasket
Was a basic engine mechanical problem found?
ÐVerify repair
Refer to
Diagnostic
Aids

6E±272
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0325
ION Sensing Module/ION Sensing Knock Intensity Circuit Fault
060R200055
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 Knock Intensity
(KI) signal pulse width if it is within a predetermined
range. If the KI 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 KI line circuit, ION 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 EST DTCs set.

No Misfire 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 condition 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 P0325 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P0325 can be cleared using the Tech2 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.

6E±273
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
If the harness appears to be OK, observe the Knock
Present, Knock Sensor Noise Channel 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 P0325 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 P0325 Diagnostic Chart may
isolate the cause of the fault.
DTC P0325 - ION Sensing Module Knock Intensity 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 P0325.
Does the Tech 2 indicate DTC P0325 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 4Ð
4Check the ION sensing harness between the PCM
(F68) and ION sensing module circuit (RED Wire) at
the KI line harness connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Disconnect the ignition coil.
Is the action complete?
ÐGo to Step 6Ð
6Check the ION sensing harness for open or short circuit
between the ignition coil and ION sensing module
circuit at the 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?
ÐGo to Step 10Go to Step 11
10Repair wiring harness.
Is the action complete?
ÐVerify repairGo to Step 11

6E±279
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation. Check for:

Poor connection ± Inspect the PCM harness and
connectors for 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, disconnectthe PCM, turn the ignition on and observe a voltmeter
connected to the 58X reference circuit at the PCM
harness connector while moving connectors and
wiring harnesses related to the PCM. A change in
voltage will indicate the location of the fault.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
DTC P0337 ± CKP Sensor Circuit Low Frequency

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Attempt to start the engine.
Does the engine start?
ÐGo to Step 3Go to Chart 3
31. Review and record Failure Records information.
2. Clear DTC P0337.
3. Start the engine and idle for 1 minute.
4. Observe DTCs.
Is DTC P0337 set?
ÐGo to Step 4
Refer to
Diagnostic
Aid
41. Disconnect the CKP sensor.
2. Ignition ªONº.
3. Using a DVM, verify that 5 V reference and ground
are being supplied at the sensor connector (PCM
side).
Are 4-6 volts and ground available at the sensor?
ÐGo to Step 7Go to Step 5
51. Ignition ªONº.
2. With a DVM, backprobe the PCM connector 5 V
reference and ground connections.
Are 5 V reference and ground available at the PCM?
ÐGo to Step 6Go to Step 11
6Check 5 V reference or ground between the CKP
sensor and PCM and repair the open circuit, short to
ground or short to voltage.
Is the action complete?
ÐVerify repairÐ
71. Ignition ªOFFº.
2. Disconnect the PCM and CKP sensor.
3. Check for an open or a short to ground in the 58X
reference circuit between the CKP sensor
connector and the PCM harness connector.
4. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
81. Reconnect the PCM and CKP sensor.
2. Connect a DVM to measure voltage on the 58X
reference circuit at the PCM connector.
3. Observe the voltage while cranking the engine.
Is the voltage near the specified value?
2.5 VGo to Step 11Go to Step 9
9Check the connections at the CKP sensor and replace
the terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 10

6E±282
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
Check for the following conditions:

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

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe theTech 2 display related to DTC P0351 while moving the
connector and wiring related to the ignition system. A
change in the display will indicate the location of the
fault.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
DTC P0351 ± Ignition 1 Control Circuit

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (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 Record
conditions as noted.
4. Use a Tech 2 to monitor the ªDTCº information for
DTC P0351 until the DTC P0351 test runs.
5. Note the test result.
Does the Tech 2 indicate DTC P0351 failed this ignition
cycle?
ÐGo to Step 3
Go to
Diagnostic
Aids
3Check for faulty connection at ignition coil.
Was a problem found?
ÐVerify repairGo to Step 4
4Check for faulty connection at PCM connector.
Was a problem found?
ÐVerify repair Go to Step 5
51. Ignition ªONº, engine ªOFFº.
2. Back probe the ignition control circuit 1 at the ION
Sensing Module with a DVM.
Is the voltage near the specified value?
25-55 mVGo to Step 6Go to Step 9
61. Ignition ªONº, engine running.
2. Back probe the ignition control circuit at the ION
Sensing Module for the cylinder being tested.
Is the voltage in the specified range, rapidly toggling
back and forth to a reading 20-50 mV higher?
100-180 mVGo to Step 7Go to Step 13
71. Ignition ªOFFº.
2. Disconnect the 3-pin and connector at the ignition
coil.
3. Check ignition control circuit 1 voltage at the ignition
coil connector while cranking the engine.
Does the voltage measure between the specified
values?
200-1200 mVGo to Step 8Go to Step 11
8Replace the ignition coil.
Is the action complete?
ÐVerify repairÐ
91. Ignition ªOFFº.
2. Disconnect the PCM and the ignition coil.
3. Check ignition control circuit 1 for short to ground.
Was a problem found?
ÐVerify repairGo to Step 10
10Check ignition control circuit 1 for short to voltage.
Was a problem found?
ÐVerify repairGo to Step 13

6E±285
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
Check for the following conditions:

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

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe theTech 2 display related to DTC P0352 while moving the
connector and wiring related to the ignition system. A
change in the display will indicate the location of the
fault.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
DTC P0352 ± Ignition 2 Control Circuit

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (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 Record
conditions as noted.
4. Use a Tech 2 to monitor the ªDTCº information for
DTC P0352 until the DTC P0352 test runs.
5. Note the test result.
Does the Tech 2 indicate DTC P0352 failed this ignition
cycle?
ÐGo to Step 3
Go to
Diagnostic
Aids
3Check for faulty connection at ignition coil.
Was a problem found?
ÐVerify repairGo to Step 4
4Check for faulty connection at PCM connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Ignition ªONº, engine ªOFFº.
2. Back probe the ignition control circuit 2 at the ION
Sensing Module with a DVM .
Is the voltage near the specified value?
25-55 mVGo to Step 6Go to Step 9
61. Ignition ªONº, engine running.
2. Back probe the ignition control circuit at the ION
Sensing Module for the cylinder being tested.
Is the voltage in the specified range, rapidly toggling
back and forth to a reading 20-50 mV higher?
100-180 mVGo to Step 7Go to Step 13
71. Ignition ªOFFº.
2. Disconnect the 3-pin connector at the ignition coil.
3. Check ignition control circuit 2 voltage at the ignition
coil connector while cranking the engine connector.
Does the voltage measure between the specified
values?
200-1200 mVGo to Step 8Go to Step 11
8Replace the ignition coil.
Is the action complete?
ÐVerify repairÐ
91. Ignition ªOFFº.
2. Disconnect the PCM and the ignition coil.
3. Check ignition control circuit 2 for short to ground.
Was a problem found?
ÐVerify repairGo to Step 10
10Check ignition control circuit 2 for short to voltage.
Was a problem found?
ÐVerify repairGo to Step 13

6E±288
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
Check for the following conditions:

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

Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe theTech 2 display related to DTC P0353 while moving the
connector and wiring related to the ignition system. A
change in the display will indicate the location of the
fault.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
DTC P0353 ± Ignition 3 Control Circuit

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (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 Record
conditions as noted.
4. Use a Tech 2 to monitor the ªDTCº information for
DTC P0353 until the DTC P0353 test runs.
5. Note the test result.
Does the Tech 2 indicate DTC P0353 failed this ignition
cycle?
ÐGo to Step 3
Go to
Diagnostic
Aids
3Check for faulty connection at ignition coil.
Was a problem found?
ÐVerify repairGo to Step 4
4Check for faulty connection at PCM connector.
Was a problem found?
ÐVerify repairGo to Step 5
51. Ignition ªONº, engine ªOFFº.
2. Back probe the ignition control circuit 3 at the ION
Sensing Module with a DVM positive lead with the
negative lead to ground.
Is the voltage near the specified value?
25-55 mVGo to Step 6Go to Step 9
61. Ignition ªONº, engine running.
2. Back probe the ignition control circuit at the ION
Sensing Module for the cylinder being tested.
Is the voltage in the specified range, rapidly toggling
back and forth to a reading 20-50 mV higher?
100-180 mVGo to Step 7Go to Step 13
71. Ignition ªOFFº.
2. Disconnect the 3-pin connector at the ignition coil.
3. Check ignition control circuit 3 voltage at the ignition
coil connector while cranking the engine.
Does the voltage measure between the specified
values?
200-1200 mVGo to Step 8Go to Step 11
8Replace the ignition coil.
Is the action complete?
ÐVerify repairÐ
91. Ignition ªOFFº.
2. Disconnect the PCM and the ignition coil.
3. Check ignition control circuit 3 for short to ground.
Was a problem found?
ÐVerify repairGo to Step 10
10Check ignition control circuit 3 for short to voltage.
Was a problem found?
ÐVerify repairGo to Step 13