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Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 325

6E–330

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0446– EVAP Canister Vent Control Malfunction

(Cont'd)

Step

Yes

Value(s)

Action

1. Disconnect the large vent hose (marked “AIR”) from

the EVAP canister.

2. Switch the rotary switch on the cart J 41413 to

“PURGE.”

3. Ignition “ON,” 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. H

Go to

Step 6

Go to

Step 8

1. 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?

—

Go to

Step 9

Go to

Step 7

Replace the EVAP canister vent solenoid.

Is the action complete?

—

Go to

Step 9

—

Replace the EVAP canister.

Is the action complete?

—

Go to

Step 9

—

1. Using Tech 2, command the EVAP canister vent

solenoid “ON” (closed).

2. Using the EVAP pressure/purge cart J 41413,

pressurize and monitor the EVAP system to 15 in.
H

3. Switch the rotary switch on cart J 41413 to “HOLD.”
4. Using the Tech 2, command the EVAP canister vent

solenoid “OFF” (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. H

Verify repair

Go 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
“ON,” allowing engine vacuum to draw a small vacuum on
the entire evaporative emissions system.

Conditions for setting the DTC

The Ignition is “ON”.

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 “OFF” 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 “Clear
Info” 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

Step

Action

Value(s)

Yes

Was the “On-Board (OBD) System Check” performed?

—

Go to

Step 2

Go to

OBD

System

Check

1. Install the Tech 2.
2. Ignition is “ON”,
3. Engine is “ON”and 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 “ON”?

—

Refer to

Diagnostic

Aids

Go to

Step 3

Check the power supply circuit.

1. Ignition is “OFF”.
2. Disconnect the canister vent solenoid valve.
3. Ignition is “ON”.
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 4

Go to

Step 5

Check the signal circuit for vent solenoid valve.

1. Ignition is “OFF”.
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?

—

Go to

Step 5

—

Repair the circuit as necessary.

Is the action complete?

—

Verify repair

—

Check 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?

—

21.8-28.5

(at

F{20

C})

—

Replace the canister vent solenoid valve.

Is the action complete?

—

Verify repair

—

Replace 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?

—

Verify repair

—

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
“ON,” allowing engine vacuum to draw a small vacuum on
the entire evaporative emissions system.

Conditions for setting the DTC

The Ignition is “ON”.

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 “OFF” 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 “Clear
Info” 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.

Content .. 323 324 325 326 ..