ISUZU AXIOM 2002 Service Repair Manual

6E±324
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0444 EVAP Purge Control Circuit Open
060RY00398
Circuit Description
The canister purge solenoid valve is controlled by the
Power Train Control Module (PCM).The PCM monitors
vacuum level via the fuel tank pressure sensor input.
At an appropriate time, the EVAP canister purge solenoid
is ªON,º allowing engine vacuum to draw a small vacuum
on the entire evaporative emissions system.
Conditions for setting the DTC

The Ignition is ªONº.

Engine is running.

System voltage is between 11.5 volts and 16 volts.
Action Taken When the DTC Sets

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

The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.
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 P0444 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P0444 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
EVAP purge solenoid 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 P0444 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 P0444 Diagnostic Chart may
isolate the cause of the fault.

6E±325
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0444 EVAP Purge Control Circuit Open

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Install the Tech 2.
2. Ignition is ªONº,
3. Engine is ªONº and operate the accelerator pedal
for 3 or 4 times.
4. Observe the EVAP purge solenoid reading on the
Tech 2.
Is the EVAP purge solenoid reading near the specified
value?
More than 1%
Refer to
Diagnostic
Aids
Go to Step 3
3Check the power supply circuit.
1. Ignition is ªOFFº.
2. Disconnect the canister purge solenoid valve.
3. Ignition is ªONº.
4. Using a DVM, measure at the EVAP purge solenoid
connector between ground and voltage supply.
Was the measurement near the specified value?
Battery
voltage
Go to Step 4Go to Step 5
4Check the signal circuit for the EVAP purge solenoid.
1. Ignition is ªOFFº.
2. Disconnect the canister purge solenoid valve.
3. Disconnect the PCM.
4. Check the circuit between EVAP purge solenoid
connector and PCM connector.
Is the problem found?
ÐGo to Step 5Go to Step 6
5Repair the circuit as necessary.
Is the action complete?
ÐVerify repairÐ
6Check the canister purge solenoid valve. Using a DVM,
measure resistance for purge solenoid valve connector
terminal.
Is the purge solenoid valve resistance within the
specified values?
25±30
(at
68
F{20
C})
Go to Step 8Go to Step 7
7Replace the canister purge solenoid valve.
Is the action complete?
ÐVerify repairÐ
8Replace the
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±326
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0445 EVAP Purge Control Circuit Short
060RY00398
Circuit Description
The canister purge solenoid valve is controlled by the
Power Train Control Module (PCM). The PCM monitors
vacuum level via the fuel tank pressure sensor input.
At an appropriate time, the EVAP canister purge solenoid
is ªON,º allowing engine vacuum to draw a small vacuum
on the entire evaporative emissions system.
Conditions for setting the DTC

The Ignition is ªONº.

Engine is running.

System voltage is between 11.5 volts and 16 volts.
Action Taken When the DTC Sets

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

The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.
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 P0445 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P0445 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
EVAP purge solenoid 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 P0445 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 P0445 Diagnostic Chart may
isolate the cause of the fault.

6E±327
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0445 EVAP Purge Control Circuit Short

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Install the Tech 2.
2. Ignition is ªONº,
3. Observe the EVAP purge solenoid reading on the
Tech 2.
Is the EVAP purge solenoid reading near the specified
value?
0%
Refer to
Diagnostic
Aids
Go to Step 3
3Check the signal circuit for canister purge solenoid
valve.
1. Ignition is ªOFFº.
2. Disconnect the canister purge solenoid valve.
3. Disconnect the PCM.
4. Check the circuit between EVAP purge solenoid
connector and PCM connector.
Is the problem found?
ÐGo to Step 4Go to Step 5
4Repair the circuit as necessary. Is the action complete?
ÐVerify repairÐ
5Check the canister purge solenoid valve.
Using a DVM, measure resistance for purge solenoid
valve connector terminal.
Is the purge solenoid valve resistance within the
specified values?
25±30 (at
68
F{20
C})
Go to Step 7Go to Step 6
6Replace the canister purge solenoid valve.
Is the action complete?
ÐVerify repairÐ
7Replace 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±328
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0446 EVAP Canister Vent Control Malfunction
060RY00398
Circuit Description
The evaporative system includes the following
components:

Fuel tank

EVAP canister vent solenoid

Fuel tank (vapor) pressure sensor

Fuel pipes and hoses

Vapor lines

Fuel cap

Evaporative emissions canister

Purge lines

EVAP canister purge solenoid
An incorrect fuel tank pressure sensor signal is detected
by monitoring fuel tank pressure when the key is first
turned ªONº during a cold start. If the fuel tank pressure
signal is out of range, DTC P0446 will set. A restricted or
blocked EVAP vent path is detected by monitoring fuel
tank pressure during normal operation (EVAP canister
vent solenoid open, EVAP canister purge solenoid
normal). With the EVAP canister vent solenoid open,
vacuum level in the system should be very low unless the
vent path is blocked. A blockage can be caused by the
following condition:

Faulty EVAP canister vent solenoid (stuck closed).

Plugged, kinked or pinched vent hose.

Shorted EVAP canister vent solenoid driver circuit.

Plugged evaporative canister.If any of these conditions are present, DTC P0446 will set.Conditions for Setting the DTC

No TP sensor, ECT sensor, Tank pressure sensor, IAT
sensor, or MAP sensor DTCs set.

Start-up engine coolant temperature and start-up
intake air temperature are more than 4
C (39
F) but
less than 34
C(93
F).

Start-up engine coolant temperature is not more than
7
C (13
F) greater than start-up intake air
temperature.

Fuel tank level is between 15% and 85%.

BARO is greater than 70 kPa.
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 set as Freeze Frame and 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 P0446 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

6E±329
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0446 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:

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.

Kinked, pinched, or plugged vent hose±Verify that the
vent hose between the EVAP canister and EVAP
canister vent solenoid is not restricted.
Reviewing the Failure Records vehicle mileage since
the diagnostic test last failed may help determinehow often the 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 a vent 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 P0446.
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.
6. Checks for a blocked EVAP canister.
DTC P0446± EVAP Canister Vent Control Malfunction

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªON.º
2. Capture Failure Records data for DTC P0446 and
clear DTCs.
3. Ignition ªOFF.º
4. Remove the fuel cap.
5. Ignition ªON.º
6. Observe ªFuel Tank Pressureº on the Tech 2.
Does 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 the EVAP
pressure/purge cart J 41413 (refer to tool operating
instructions).
7. Replace the fuel cap.
8. Using the Tech 2, command the EVAP vent
solenoid ªONº (closed).
9. Connect the EVAP pressure/purge cart J 41413 to
the EVAP service port.
10.Using the EVAP pressure/purge cart J 41413,
pressurize the EVAP system to the specified value.
11. Observe ªFuel Tank Pressureº on the Tech 2.
Does Tech 2 indicate ªFuel Tank Pressureº at the
specified value?
1.52 ± 1.69VGo to Step 4
Go to Fuel
Tank
Pressure
System
41. Maintain the EVAP pressure at 5 in. at H2O.
2. Using Tech 2, command the EVAP vent solenoid
ªOFFº (open) while observing the EVAP pressure
gauge on the cart J 41413.
Does the EVAP pressure return to the specified value
within 5 seconds?
0 in. H2O
Refer to
Diagnostic
Aids
Go to Step 5

6E±330
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0446± EVAP Canister Vent Control Malfunction

 
StepNo Ye s Value(s) Action
51. Disconnect the large vent hose (marked ªAIRº) from
the EVAP canister.
2. Switch the rotary switch on the cart J 41413 to
ªPURGE.º
3. Ignition ªON,º engine idling at normal operating
temperature.
4. Observe vacuum gauge for 5 seconds while holding
the engine speed at 2500 RPM.
Does the vacuum remain less than the specified value?
30 in. H2OGo to Step 6Go to Step 8
61. Inspect the vent hose between the EVAP canister
and the EVAP canister vent solenoid for kinks,
pinched areas, or any other form of blockage.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐGo to Step 9Go to Step 7
7Replace the EVAP canister vent solenoid.
Is the action complete?
ÐGo to Step 9Ð
8Replace the EVAP canister.
Is the action complete?
ÐGo to Step 9Ð
91. Using Tech 2, command the EVAP canister vent
solenoid ªONº (closed).
2. Using the EVAP pressure/purge cart J 41413,
pressurize and monitor the EVAP system to 15 in.
H
2O.
3. Switch the rotary switch on cart J 41413 to ªHOLD.º
4. Using the Tech 2, command the EVAP canister vent
solenoid ªOFFº (open) while observing the EVAP
pressure gauge on cart J 41413.
Does the EVAP pressure return to the specified value
within 5 seconds?
0 in. H2OVerify repairGo to Step 2

6E±331
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0447 EVAP Vent Solenoid Circuit Open
060RY00398
Circuit Description
The canister purge solenoid valve is controlled by the
Power Train Control Module (PCM).The PCM monitors
vacuum level via the fuel tank pressure sensor input.
At an appropriate time, the EVAP canister vent solenoid is
ªON,º allowing engine vacuum to draw a small vacuum on
the entire evaporative emissions system.
Conditions for setting the DTC

The Ignition is ªONº.

Engine is running.

System voltage is between 11.5 volts and 16 volts.
Action Taken When the DTC Sets

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

The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.
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 P0447 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P0447 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
EVAP vent valve 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 P0447 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 P0447 Diagnostic Chart may
isolate the cause of the fault.

6E±332
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0447 EVAP Vent Solenoid Circuit Open

StepActionValue(s)Ye sNo
1Was the ªOn-Board (OBD) System Checkº performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Install the Tech 2.
2. Ignition is ªONº,
3. Engine is ªONºand operate the acceleration pedal
for 3 or 4 times.
4. Observe the EVAP vent solenoid reading on the
Tech 2.
Is the EVAP vent solenoid reading to ªONº?
Ð
Refer to
Diagnostic
Aids
Go to Step 3
3Check the power supply circuit.
1. Ignition is ªOFFº.
2. Disconnect the canister vent solenoid valve.
3. Ignition is ªONº.
4. Using a DVM, measure at the EVAP vent solenoid
connector between ground and voltage supply.
Was the measurement near the specified value?
Battery
voltage
Go to Step 4Go to Step 5
4Check the signal circuit for vent solenoid valve.
1. Ignition is ªOFFº.
2. Disconnect the canister vent solenoid valve.
3. Disconnect the PCM.
4. Check the circuit between EVAP vent solenoid
connector and PCM connector.
Is the problem found?
ÐGo to Step 5Ð
5Repair the circuit as necessary.
Is the action complete?
ÐVerify repairÐ
6Check the canister vent solenoid valve.
Using a DVM, measure resistance for vent solenoid
valve connector terminal.
Is the vent solenoid valve resistance within the
specified values?
Ð
21.8-28.5

(at
68
F{20
C})
Ð
7Replace the canister vent solenoid valve.
Is the action complete?
ÐVerify repairÐ
8Replace 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±333
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P0448 EVAP Vent solenoid Circuit Short
060RY00398
Circuit Description
The canister purge solenoid valve is controlled by the
Power Train Control Module (PCM). The PCM monitors
vacuum level via the fuel tank pressure sensor input.
At an appropriate time, the EVAP canister vent solenoid is
ªON,º allowing engine vacuum to draw a small vacuum on
the entire evaporative emissions system.
Conditions for setting the DTC

The Ignition is ªONº.

Engine is running.

System voltage is between 11.5 volts and 16 volts.
Action Taken When the DTC Sets

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

The PCM will store conditions which were present
when the DTC was set in the Failure Records data only.
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 P0448 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.
DTC P0448 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
EVAP vent valve 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 P0448 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 P0448 Diagnostic Chart may
isolate the cause of the fault.