OBD port ISUZU AXIOM 2002 Service Owner's Guide

6E±246
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0203 ± Injector 3 Control Circuit

 
StepNo Ye s Value(s) Action
6Note whether the injector test light for cylinder 3 was
ªOFFº or ªONº steady in step 5.
Was the test light ªONº steady while cranking the
engine?
ÐGo to Step 7Go to Step 9
71. Disconnect the PCM connector for the affected
injectors.
2. With a test light connected to B+, probe the affected
injector driver circuit.
Does the test light illuminate?
ÐGo to Step 8Go to Step 15
8Repair short to ground in the injector driver circuit.
Is the action complete?
Ð
Go to OBD
System
Check
Ð
91. Disconnect the injector test connector.
2. At the injector side of the harness, connect an
ohmmeter between the positive wire (red with blue
tracer) and the wire for cylinder 3 (green).
Does the ohmmeter indicate continuity?
ÐGo to Step 11Go to Step 10
10Repair the open injector harness wire or open injector.
Is the action complete?
ÐVerify repairÐ
11At the PCM side of the injector test connector, check
the green wire for a short to voltage.
Was there a short to voltage?
ÐGo to Step 12Go to Step 13
12Repair the short to voltage.
Is the action complete?
ÐVerify repairÐ
13Check for an open circuit between the injector test
connector and the PCM.
Was there an open circuit?
ÐGo to Step 14Go to Step 15
14Repair the open circuit.
Is the action complete?
ÐVerify repairÐ
15Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to the 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±249
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0204 ± Injector 4 Control Circuit

 
StepNo Ye s Value(s) Action
6Note whether the injector test light for cylinder 4 was
ªOFFº or ªONº steady in step 5.
Was the test light ªONº steady while cranking the
engine?
ÐGo to Step 7Go to Step 9
71. Disconnect the PCM connector for the affected
injectors.
2. With a test light connected to B+, probe the affected
injector driver circuit.
Does the test light illuminate?
ÐGo to Step 8Go to Step 15
8Repair short to ground in the injector driver circuit.
Is the action complete?
Ð
Go to OBD
System
Check
Ð
91. Disconnect the injector test connector.
2. At the injector side of the harness, connect an
ohmmeter between the positive wire (red with blue
tracer) and the wire for cylinder 4 (green/red).
Does the ohmmeter indicate continuity?
ÐGo to Step 11Go to Step 10
10Repair the open injector harness wire or open injector.
Is the action complete?
ÐVerify repairÐ
11At the PCM side of the injector test connector, check
the green/red wire for a short to voltage.
Was there a short to voltage?
ÐGo to Step 12Go to Step 13
12Repair the short to voltage.
Is the action complete?
ÐVerify repairÐ
13Check for an open circuit between the injector test
connector and the PCM.
Was there an open circuit?
ÐGo to Step 14Go to Step 15
14Repair the open circuit.
Is the action complete?
ÐVerify repairÐ
15Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to the 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±252
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0205 ± Injector 5 Control Circuit

 
StepNo Ye s Value(s) Action
6 Note whether the injector test light for cylinder 5 was
ªOFFº or ªONº steady in step 5.
Was the test light ªONº steady while cranking the
engine?
ÐGo to Step 7Go to Step 9
71. Disconnect the PCM connector for the affected
injectors.
2. With a test light connected to B+, probe the affected
injector driver circuit.
Does the test light illuminate?
ÐGo to Step 8Go to Step 15
8Repair short to ground in the injector driver circuit.
Is the action complete?
Ð
Go to OBD
System
Check
Ð
91. Disconnect the injector test connector.
2. At the injector side of the harness, connect an
ohmmeter between the positive wire (red with blue
tracer) and the wire for cylinder 5 (green with black
tracer).
Does the ohmmeter indicate continuity?
ÐGo to Step 11Go to Step 10
10Repair the open injector harness wire or open injector.
Is the action complete?
ÐVerify repairÐ
11At the PCM side of the injector test connector, check
the green/black wire for a short to voltage.
Was there a short to voltage?
ÐGo to Step 12Go to Step 13
12Repair the short to voltage.
Is the action complete?
ÐVerify repairÐ
13Check for an open circuit between the injector test
connector and the PCM.
Was there an open circuit?
ÐGo to Step 14Go to Step 15
14Repair the open circuit.
Is the action complete?
ÐVerify repairÐ
15Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to the 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±255
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0206 ± Injector 6 Control Circuit

 
StepNo Ye s Value(s) Action
6Note whether the injector test light for cylinder 6 was
ªOFFº or ªONº steady in step 5.
Was the test light ªONº steady while cranking the
engine?
ÐGo to Step 7Go to Step 9
71. Disconnect the PCM connector for the affected
injectors.
2. With a test light connected to B+, probe the affected
injector driver circuit.
Does the test light illuminate?
ÐGo to Step 8Go to Step 15
8Repair short to ground in the injector driver circuit.
Is the action complete?
Ð
Go to OBD
System
Check
Ð
91. Disconnect the injector test connector.
2. At the injector side of the harness, connect an
ohmmeter between the positive wire (red with blue
tracer) and the wire for cylinder 6 (green with yellow
tracer).
Does the ohmmeter indicate continuity?
ÐGo to Step 11Go to Step 10
10Repair the open injector harness wire or open injector
Is the action complete?
ÐVerify repairÐ
11At the PCM side of the injector test connector, check
the green/yellow wire for a short to voltage.
Was there a short to voltage?
ÐGo to Step 12Go to Step 13
12Repair the short to voltage.
Is the action complete?
ÐVerify repairÐ
13Check for an open circuit between the injector test
connector and the PCM.
Was there an open circuit?
ÐGo to Step 14Go to Step 15
14Repair the open circuit.
Is the action complete?
ÐVerify repairÐ
15Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to the 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±277
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0336 ± 58X Reference Signal Circuit

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 3
Go to ªEngine
Cranks But
Will Not Runº
chart
31. Review and record Failure Records information.
2. Clear DTC P0336.
3. Start the engine and idle for 1 minute.
4. Observe DTCs.
Is DTC P0336 set?
ÐGo to Step 4
Refer to
Diagnostic
Aids
41. Disconnect the PCM and CKP sensor.
2. Check for an open or a short to ground in the 58X
reference circuit between the CKP sensor
connector and the PCM harness connector.
3. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 5
51. 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 8Go to Step 6
6Check the connections at the CKP sensor and replace
the terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 7
7Replace the CKP sensor. Use caution to avoid any hot
oil that may drip out.
Is the action complete?
ÐVerify repairÐ
8Check connections at the PCM and replace the
terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 9
9Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain 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±301
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0401 ± EGR Flow Insufficient

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Is DTC P1404 also set?
Ð
Go to DTC
1404
Go to Step 3
31. Start the engine.
2. Monitor the MAP signal with a Tech 2 while idling.
3. While idling, jab the accelerator pedal about halfway
down and immediately let the engine return to idle.
Did the MAP value on the Tech 2 show an immediate
large change?
ÐGo to Step 5Go to Step 4
4Replace the MAP sensor.
Is the action complete?
ÐVerify repairÐ
51. Inspect the exhaust system for modification of
original installed parts or leaks.
2. If a problem was found, repair exhaust system as
necessary.
Was a condition present that required repair?
ÐGo to Step 8Go to Step 6
61. Remove the EGR valve.
2. Visually and physically inspect the pintle, valve
passages and the adapter for excessive deposits or
any kind of a restriction.
3. If a problem is found, clean or replace EGR system
components as necessary.
Was a condition present that required repair?
ÐGo to Step 8Go to Step 7
71. Remove the EGR inlet and outlet pipes from the
exhaust manifold and the intake manifold.
2. Inspect the manifold EGR ports and the EGR inlet
and outlet pipes for a blockage caused by excessive
deposits or other damage.
3. If a problem is found, correct the condition as
necessary.
Was a condition present that required repair?
ÐGo to Step 8
Refer to
Diagnostic
Aids
81. Review and record the Tech 2 Failure Records data.
2. Clear DTC and monitor the Tech 2 System Info
Screen while operating the vehicle as specified in
ªDiagnostic Aidsº.
3. Using a Tech 2, monitor ªDTCº info for DTC P0401
until the DTC P0401 test runs.
4. Note the test result.
Does the Tech 2 indicate DTC P0401 failed this
ignition?
ÐÐ
Repair
complete

6E±305
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0404 ± EGR Open Stuck

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, review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor ªDTCº info for DTC P0404
until the DTC P0404 test runs. Note the result.
Does the Tech 2 indicates DTC P0404 failed this
ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
ÐGo to Step 4Go to Step 5
4Repair the damaged pin or terminal.
ÐVerify repair
Is the action
complete?
51. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any excessive
carbon deposit on EGR shaft.
Was excessive carbon deposit on EGR valve shaft?
ÐGo to Step 6Go to Step 7
61. Clean up EGR valve shaft and inside of EGR valve.
2. Visually inspect damage of pintle and seat if is bent,
leakage may occur.
Was there any severe damage which affects function?
ÐGo to Step 8
Verify repair
Go to
Step 7
71. Reconnect.
2. Ignition ªOFFº.
3. Install the Tech 2.
4. Run the engine at idle.
5. On the Tech 2, select EGR Control Test.
6. Use the ªUPº arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
ÐÐGo to Step 8
8Replace the EGR valve.
Does DTC P0404 still fail ªDTCº test on the Tech 2?
ÐGo to Step 9Verify repair
9Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain 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±314
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0420 ± TWC System Low Efficiency Bank 1

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any other DTCs set (such as P0140)?
Ð
Diagnose
other DTC(s)
first
Go to Step 3
31. Visually and physically inspect the three-way
catalytic converter for damage. Check for the
following:

dents

severe discoloration caused by excessive
temperatures

holes

internal rattle caused by damaged catalyst
2. Also, ensure that the three-way catalytic converter
is a proper original equipment manufacturer part.
Did your inspection reveal a problem?
ÐGo to Step 6Go to Step 4
41. Visually and physically inspect the exhaust system
between the three-way catalytic converter and the
rear converter flange for leaks, damage, and loose
or missing hardware.
2. If a problem is found, repair as necessary.
Did your inspection reveal a problem?
Ð
Go to Step 7
to verify
repair
Go to Step 5
51. Visually and physically inspect the Bank 1 HO2S 2.
2. Ensure that the Bank 1 HO2S 2 is secure and that
the pigtail and wiring harness is not contacting the
exhaust pipe or is not otherwise damaged.
3. If a problem is found, repair as necessary.
Did your inspection reveal a problem?
Ð
Go to Step 7
to verify
repair
Go to Step 6
6Replace the three-way catalytic converter.
NOTE: Check for conditions which may cause catalyst
damage (refer to
Diagnostic Aids).
Is the action complete?
Ð
Go to Step 7
to verify
repair
Ð
71. Review and record the Tech 2 Failure Records data.
2. Clear DTC P0420.
3. Start the engine and allow it to warm up until the
engine coolant temperature monitored on the Tech
2 is above the specified value.
4. Run the engine to maintain the specified mass air
flow range for at least 2 minutes.
5. Operate the vehicle to maintain DTC P0420 test
conditions (refer to
DTC Test Description in
Diagnostic Support for detailed instructions).
6. Using a Tech 2, monitor ªDTCº info for DTC P0420
until the DTC P0420 test runs.
7. Note the test result.
Does the Tech 2 indicate DTC P0420 passed this
ignition?
Engine
coolant temp:
greater than
60
C
(140
F).
Mass air flow:
between 8
g/second and
50 g/second
Complete
repair. If a
driveability
symptom still
exists, refer
to
Symptoms.
Go to the
Diagnostic
Aids

6E±317
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0430 ± TWC System Low Efficiency Bank 2

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any other DTCs set (such as P0160)?
Ð
Diagnose
other DTC(s)
first
Go to Step 3
31. Visually and physically inspect the three-way
catalytic converter for damage. Check for the
following:

dents

severe discoloration caused by excessive
temperatures

holes

internal rattle caused by damaged catalyst
2. Also, ensure that the three-way catalytic converter
is a proper original equipment manufacturer part.
Did your inspection reveal a problem?
ÐGo to Step 6Go to Step 4
41. Visually and physically inspect the exhaust system
between the three-way catalytic converter and the
rear converter flange for leaks, damage, and loose
or missing hardware.
2. If a problem is found, repair as necessary.
Did your inspection reveal a problem?
Ð
Go to Step 7
to verify
repair
Go to Step 5
51. Visually and physically inspect the Bank 2 HO2S 2.
2. Ensure that the Bank 2 HO2S 2 is secure and that
the pigtail and wiring harness is not contacting the
exhaust pipe or is not otherwise damaged.
3. If a problem is found, repair as necessary.
Did your inspection reveal a problem?
Ð
Go to Step 7
to verify
repair
Go to Step 6
6Replace the three-way catalytic converter.
NOTE: Check for conditions which may cause catalyst
damage (refer to
Diagnostic Aids).
Is the action complete?
Ð
Go to Step 7
to verify
repair
Ð
71. Review and record the Tech 2 Failure Records data.
2. Clear DTC P0430.
3. Start the engine and allow it to warm up until the
engine coolant temperature monitored on the Tech
2 is above the specified value.
4. Run the engine to maintain the specified mass air
flow range for at least 6 minutes.
5. Operate the vehicle to maintain DTC P0430 test
conditions (refer to
DTC Test Description in
Diagnostic Support for detailed instructions).
6. Using a Tech 2, monitor ªDTCº info for DTC P0430
until the DTC P0430 test runs.
7. Note the test result.
Does the Tech 2 indicate DTC P0430 passed this
ignition?
Engine
coolant temp:
greater than
70
C
(158
F).
Mass air flow:
between 2.5
g/second and
10 g/second
Complete
repair. If a
driveability
symptom still
exists, refer
to
Symptoms.
Go to the
Diagnostic
Aids

6E±322
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Aids
Check for the following conditions:

Cracked or punctured EVAP canister.

Damaged source vacuum line, EVAP purge line, EVAP
vent hose or fuel tank vapor line.

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 to the
EVAP canister vent solenoid, EVAP canister purge
solenoid and the fuel tank pressure sensor for an
intermittent open or short circuit.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how oftenthe condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. If an EVAP canister vent solenoid or an EVAP
canister purge solenoid electrical fault is present,
the purge system will not operate correctly.
Repairing the electrical fault will very likely correct
the condition that set DTC P0442.
3. Checks the fuel tank pressure sensor at ambient
pressure.
4. Verifies that the fuel tank pressure sensor accurately
reacts to EVAP system pressure changes.
DTC P0442 ± EVAP System Leak Detected

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªOFFº.
2. Remove the fuel cap.
3. Ignition ªONº.
4. Observe ªFuel Tank Pressureº on the Tech 2.
Does the Tech 2 indicate ªFuel Tank Pressureº at the
specified value?
1.51VGo to Step 3
Go to Fuel
Tank
Pressure
System
3IMPORTANT:Before continuing with diagnosis, zero
the EVAP pressure and vacuum gauges on EVAP
pressure/purge cart J 41413 (refer to tool operating
instructions).
1. Replace the fuel cap.
2. Capture Failure Records data for DTC P0442 and
clear DTCs.
3. Connect the EVAP pressure/purge cart J 41413 to
the EVAP service port.
4. Using the Tech 2, command the EVAP canister vent
solenoid ªONº (closed).
5. Using the EVAP pressure/purge cart J 41413,
pressurize the EVAP system to the specified value.
6. Observe ªFuel Tank Pressureº on the Tech 2.
Does the Tech 2 indicate ªFuel Tank Pressureº at the
specified value?
1.47VGo to Step 4
Go to Fuel
Tank
Pressure
System
41. Ignition ªONº, engine idling.
2. Using the Tech 2, command the EVAP canister vent
solenoid ªONº (closed).
3. Using the EVAP pressure/purge cart J 41413,
pressurize the EVAP system to 15 in. H
2O.
4. Switch the rotary switch on the cart to ªHOLDº and
observe the EVAP pressure gauge.
Does the pressure decrease to less than the specified
value within 2 minutes?
1.47 ± 1.51VGo to Step 5
Refer to
Diagnostic
Aids