P0456

P0456 EVAP CONTROL SYSTEM

DTC Logic


DTC DETECTION LOGIC

NOTE:
If DTC P0456 is displayed with DTC P0442, first perform the trouble diagnosis for DTC P0456.
This diagnosis detects very small leaks in the EVAP line between fuel tank and EVAP canister purge volume control solenoid valve, using the intake manifold vacuum in the same way as conventional EVAP small leak diagnosis.
If ECM judges a leak which corresponds to a very small leak, the very small leak P0456 will be detected.
If ECM judges a leak equivalent to a small leak, EVAP small leak P0442 will be detected.
If ECM judges that there are no leaks, the diagnosis will be OK.











CAUTION:
- Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the
MIL may illuminate.
- If the fuel filler cap is not tightened properly, the MIL may illuminate.
- Use only a genuine NISSAN rubber tube as a replacement.

DTC CONFIRMATION PROCEDURE


1. INSPECTION START

Will CONSULT be used?
Will CONSULT be used?
YES- GO TO 2.
NO- GO TO 4.

2. PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1.Turn ignition switch OFF and wait at least 10 seconds.
2.Turn ignition switch ON.
3.Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
After repair, check that the hoses and clips are installed properly.
TESTING CONDITION:
-Open engine hood before conducting the following procedure.
-If any of following conditions are met just before the DTC confirmation procedure, leave the vehicle for more than 1 hour.
-Fuel filler cap is removed.
-Fuel is refilled or drained.
-EVAP component part/parts is/are removed.
-Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.
-Check that EVAP hoses are connected to EVAP canister purge volume control solenoid valve properly.
- GO TO 3.

3. PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT
1.Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT.
2.Check that the following conditions are met.







If NG, turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle), or refill/drain fuel until the output voltage condition of the "FUEL LEVEL SE" meets within the range above and leave the vehicle for more than 1 hour. Then start from step 1.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Turn ignition switch ON.
5.Select "EVP V/S LEAK P0456/P1456" of "EVAPORATIVE SYSTEM" in "DTC WORK SUPPORT" mode with CONSULT.
Follow the instructions displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on CONSULT screen, go to
Basic Inspection.
Which is displayed on CONSULT screen?
OK- INSPECTION END
NG- Proceed to .

4. PERFORM COMPONENT FUNCTION CHECK

With GST
Perform component function check. .
NOTE:
Use component function check to check the overall function of the EVAP very small leak function. During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to .


Component Function Check


1. PERFORM COMPONENT FUNCTION CHECK

With GST

CAUTION:
- Never use compressed air, doing so may damage the EVAP system.
- Never start engine.
- Never exceed 4.12 kPa (0.042 kg/cm, 0.6 psi).
1.Attach the EVAP service port adapter securely to the EVAP service port (commercial service tool).





2.Set the pressure pump and a hose.
3.Also set a vacuum gauge via 3-way connector and a hose.
4.Turn ignition switch ON.
5.Connect GST and select Service $08.
6.Using Service $08 control the EVAP canister vent control valve (close).
7.Apply pressure and check the following conditions are satisfied.







Is the inspection result normal?
YES- GO TO 2.
NO- Proceed to .

2. RELEASE PRESSURE

1.Disconnect GST.
2.Start engine and warm it up to normal operating temperature.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Turn ignition switch ON.
5.Turn ignition switch OFF and wait at least 10 seconds.
6.Restart engine and let it idle for 90 seconds.
7.Keep engine speed at 2,000 rpm for 30 seconds.
8.Turn ignition switch OFF.
NOTE:
For more information, refer to GST Instruction Manual.
- INSPECTION END


Diagnosis Procedure


1. CHECK FUEL FILLER CAP DESIGN

1.Turn ignition switch OFF.





2.Check for genuine NISSAN fuel filler cap design.
Is the inspection result normal?
YES- GO TO 2.
NO- Replace with genuine NISSAN fuel filler cap.

2. CHECK FUEL FILLER CAP INSTALLATION

Check that the cap is tightened properly by rotating the cap clockwise.
Is the inspection result normal?
YES- GO TO 3.
NO- Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. Retighten until ratcheting sound is heard.

3. CHECK FUEL FILLER CAP FUNCTION

Check for air releasing sound while opening the fuel filler cap.
Is the inspection result normal?
YES- GO TO 5.
NO- GO TO 4.

4. CHECK FUEL TANK VACUUM RELIEF VALVE

.
Is the inspection result normal?
YES- GO TO 5.
NO- Replace fuel filler cap with a genuine one.

5. CHECK FOR EVAP LEAK

Testing and Inspection.
Is there any leak in EVAP line?
YES- Repair or replace malfunctioning part.
NO- GO TO 6.

6. CHECK EVAP CANISTER VENT CONTROL VALVE

Check the following.
- EVAP canister vent control valve is installed properly.
Removal and Installation.
- EVAP canister vent control valve.
P0447.
Is the inspection result normal?
YES- GO TO 7.
NO- Repair or replace EVAP canister vent control valve and O-ring.

7. CHECK IF EVAP CANISTER IS SATURATED WITH WATER

1.Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.





2.Check if water will drain from EVAP canister (1).





Does water drain from the EVAP canister?
YES- GO TO 8.
NO-1- With CONSULT: GO TO 10.
NO-2- Without CONSULT: GO TO 11.

8. CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor attached.






Is the inspection result normal?
YES-1- With CONSULT: GO TO 10.
YES-2- Without CONSULT: GO TO 11.
NO- GO TO 9.

9. DETECT MALFUNCTIONING PART

Check the following.
- EVAP canister for damage
- EVAP hose between EVAP canister and vehicle frame for clogging or poor connection
- Repair hose or replace EVAP canister. Removal and Installation.

10. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT

1.Disconnect vacuum hose connected to EVAP service port and EVAP canister purge volume control solenoid valve from EVAP canister purge volume control solenoid valve.
2.Start engine and let it idle.
3.Select "PURG VOL CONT/V" in "ACTIVE TEST" mode.
4.Touch "Qu" on CONSULT screen to increase "PURG VOL CONT/V" opening to 100%.
5.Check vacuum hose for vacuum.

Vacuum should exist.

Is the inspection result normal?
YES- GO TO 13.
NO- GO TO 12.

11. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

Without CONSULT

1.Start engine and warm it up to normal operating temperature.
2.Stop engine.
3.Disconnect vacuum hose connected to EVAP service port and EVAP canister purge volume control solenoid valve from EVAP canister purge volume control solenoid valve.
4.Start engine and let it idle for at least 80 seconds.
5.Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
Vacuum should exist.
Is the inspection result normal?
YES- GO TO 14.
NO- GO TO 12.

12. CHECK VACUUM HOSE

Check vacuum hoses for clogging or disconnection. System Diagram.
Is the inspection result normal?
YES- GO TO 13.
NO- Repair or reconnect the hose.

13. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

P0443.
Is the inspection result normal?
YES- GO TO 14.
NO- Replace EVAP canister purge volume control solenoid valve. Exploded View.

14. CHECK FUEL TANK TEMPERATURE SENSOR

P0181.
Is the inspection result normal?
YES- GO TO 15.
NO- Replace "fuel level sensor unit and fuel pump". Removal and Installation.

15. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

P0451.
Is the inspection result normal?
YES- GO TO 16.
NO- Replace EVAP control system pressure sensor. Removal and Installation.

16. CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
System Diagram.
Is the inspection result normal?
YES- GO TO 17.
NO- Repair or reconnect the hose.

17. CLEAN EVAP PURGE LINE

Clean EVAP purge line (pipe and rubber tube) using air blower.
- GO TO 18.

18. CHECK EVAP/ORVR LINE

Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kinks, looseness and improper connection. For location, Testing and Inspection.
Is the inspection result normal?
YES- GO TO 19.
NO- Repair or replace hoses and tubes.

19. CHECK RECIRCULATION LINE

Check recirculation line between filler neck tube and fuel tank for clogging, kinks, cracks, looseness and improper connection.
Is the inspection result normal?
YES- GO TO 20.
NO- Repair or replace hose, tube or filler neck tube.

20. CHECK REFUELING EVAP VAPOR CUT VALVE

Testing and Inspection.
Is the inspection result normal?
YES- GO TO 21.
NO- Replace refueling EVAP vapor cut valve with fuel tank. Removal and Installation.

21. CHECK FUEL LEVEL SENSOR

Fuel Level Sensor Signal Circuit.
Is the inspection result normal?
YES- GO TO 22.
NO- Replace "fuel level sensor unit and fuel pump (main)". Removal and Installation.

22. CHECK INTERMITTENT INCIDENT

Perform Intermittent Incident.
- INSPECTION END


Component Inspection


1. CHECK FUEL FILLER CAP

1.Turn ignition switch OFF.
2.Remove fuel filler cap.





3.Wipe clean valve housing.





4.Install fuel filler cap adapter (commercial service tool) to fuel filler cap.
5.Check valve opening pressure and vacuum.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 2.

2. REPLACE FUEL FILLER CAP

Replace fuel filler cap.

CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may illuminate.
- INSPECTION END