Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 825

6E–324

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

D

A history DTC P0456 will clear after 40 consecutive trip
cycle during which the warm up cycles have occurred
without a fault.

D

DTC P0456 can be cleared using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

Cracked or punctured EVAP canister.

D

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

D

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.

D

Damaged harness-Inspect the wiring harness to the
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 often the condition that caused the DTC to be
set occurs.

This may assist in diagnosing the condition.

Diagnostic Trouble Code(DTC)P0456 EVAP Very Small  Leak

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “OFF”.
2. Remove the fuel cap.
3. Ignition “ON”.
4. Observe “Fuel Tank Pressure” on the Tech 2.

Does the Tech 2 indicate “Fuel Tank Pressure” at the
specified value?

1.51V

Go to 

Step 3

Go to 

Fuel

Tank

Pressure

System

3

1. Visually/physically check for the following

conditions:

D

Vent hose disconnected or damaged.

D

EVAP canister damaged.

D

Fuel cap damaged

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 4

4

1. Ignition “ON”, engine “OFF”.
2. Install the fuel cap.
3. Review and record Tech 2 Failure Records data.
4. Operate the vehicle within Failure Records

conditions as noted.

5. Using theTech 2,monitor the “DTC” info for DTC

P0456.

Does the Tech 2 indicate DTC P0456?

—

Go to 

Step 5

Check the

Procedure

Refer to

Diagnostic

Aids

5

1. Ignition “ON”, engine idling.
2. Observe “Fuel Tank Pressure” on the Tech 2.

Does the Tech 2 indicate “Fuel Tank Pressure” at the
specified value?

—

Check the

Procedure

Refer to

Diagnostic

Aids

Go to 

Step 6

6E–325

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code(DTC)P0456 EVAP Very Small  Leak

  (Cont'd)

Step

No

Yes

Value(s)

Action

6

1. Ignition “ON”, engine idling.
2. Using theTech 2, command the EVAP canister vent

solenoid “ON” (closed)

3. Observe “EVAP canister vent solenoid operation”

second value?

4. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to 

Step 7

7

1. Visually/physically check for the following

conditions:

D

Disconnected or leaking fuel tank vapor line.

D

Disconnected or damaged EVAP purge line.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Check the

Procedure

Refer to

Diagnostic

Aids

6E–326

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) 

P0461 Fuel Level Sensor Performance

D06R200091

Circuit Description

The fuel level sensor is an important input to powertrain
control module (PCM) for the enhanced evaporative
system diagnostic.  Fuel level information is needed for
the PCM to know the volume of fuel in the tank.  The fuel
level affects the rate of change in air pressure in the
evaporative system.
The sending unit is a float in the fuel tank which moves a
wiper arm across a variable resistor.  Low fuel level
causes high resistance in the sending unit, and this is
recognized by the PCM because the circuit operates at a
corresponding low voltage.  When the circuit is
continuously open or has a high resistance connection,
DTC P0461 is set.

Conditions for Setting the DTC

D

Sensor output change is more than 2% within 200km.
Or Sensor movement position change is less than
15% within 200km.

D

IAT is more than 0

°

C.

D

MAP changing in 3 sec is less than 10kPa.

D

Engine speed changing in 3 sec is less than 50rpm.

When there are 12 test failures within 80 test samples, it is
stored.

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

D

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 DTC

D

DTC P0461 can be cleared by using the scan tool
“Clear Info” function or by disconnecting the PCM
battery feed.

Diagnostic Aids

D

Damaged harness–Inspect the wiring harness for
damage.  If the harness appears to be OK, observe the
fuel level display on the scan tool while moving
connectors and wiring harnesses related to the sensor.
A change in the display will indicate the location of the
fault.

6E–327

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0461– Fuel Level Sensor Performance

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “Off”, Engine “Off”.
2. Install Tech 2.
3. Ignition “On”, Engine “Off”.
4. Check DTC P0462, P0463.

Was the DTC stored?

—

Go to

applicable
DTC table

Go to 

Step 3

3

Check DTC P0464.

Was the DTC stored?

—

Go to 

DTC

P464 table

Go to 

Step 4

4

1. Ignition “Off”, Engine “Off”.
2. Replace the fuel level sensor.

Was the action complete?

—

Verify repair

—