P0456

P0456 EVAP CONTROL SYSTEM

DTC Logic


DTC DETECTION LOGIC

This diagnosis detects leaks in the EVAP line between fuel tank and EVAP canister purge volume control solenoid valve, using the negative pressure caused by decrease of fuel temperature in the fuel tank after turning ignition switch OFF.
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. PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following 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.
Do you have CONSULT?
YES- GO TO 2.
NO- GO TO 4.

2. PERFORM DTC CONFIRMATION PROCEDURE-I

With CONSULT
1.Turn ignition switch ON and select "EVAP DIAG READY" in "DATA MONITOR" mode with CONSULT.
2.Start engine and wait at idle until "OFF" of "EVAP DIAG READY" changes to "ON".
NOTE:
It will take at most 2 hours until "OFF" of "EVAP DIAG READY" changes to "ON".
3.Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
4.Turn ignition switch ON and select "EVAP LEAK DIAG" in "DATA MONITOR" mode with CONSULT.
5.Check that "EVAP LEAK DIAG" indication.
Which is displayed on CONSULT?
CMPLT- GO TO 3.
YET- Perform DTC CONFIRMATION PROCEDURE again. GO TO 1.

3. PERFORM COMPONENT FUNCTION CHECK-II

Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Go to "Diagnosis Procedure" .
NO- INSPECTION END

4. PERFORM DTC CONFIRMATION PROCEDURE

With GST
1.Start engine and wait engine idle for at least 2 hours.
2.Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
3.Turn ignition switch ON.
4.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Go to "Diagnosis Procedure" .
NO- 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. Refer to
"Exploded View" Exploded View.

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. Then 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

Refer to "Component Inspection" Testing and Inspection.
Is the inspection result normal?
YES- GO TO 5.
NO- Replace fuel filler cap with a genuine one. Refer to "Exploded View" Exploded View.

5. CHECK FOR EVAP LEAK

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

6. CHECK EVAP CANISTER VENT CONTROL VALVE

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

7. CHECK IF EVAP CANISTER IS SATURATED WITH WATER






1.Remove EVAP canister (1) with EVAP canister vent control valve (2) and EVAP control system pressure sensor attached.
2.Check if water will drain from EVAP canister.
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 assembly 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. Refer to "Removal and Installation" 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 service port.
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 C/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 service port.
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 13.
NO- GO TO 12.

12. CHECK VACUUM HOSE

Check vacuum hoses for clogging or disconnection. Refer to "System Diagram" 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

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

14. CHECK FUEL TANK TEMPERATURE SENSOR

Refer to "Component Inspection" P0181.
Is the inspection result normal?
YES- GO TO 15.
NO- Replace fuel level sensor unit. Refer to "Exploded View" Exploded View.

15. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to "Component Inspection" P0451.
Is the inspection result normal?
YES- GO TO 16.
NO- Replace EVAP control system pressure sensor. Refer to "Exploded View" Exploded View.

16. CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to "System Diagram" 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, refer to "Description" 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

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

21. CHECK FUEL LEVEL SENSOR

Refer to "Component Inspection" Fuel Level Sensor Signal Circuit.
Is the inspection result normal?
YES- GO TO 22.
NO- Replace fuel level sensor unit. Refer to "Removal and Installation" Removal and Installation.

22. CHECK INTERMITTENT INCIDENT

Refer to "Intermittent Incident" Intermittent Incident.
- INSPECTION END


Component Inspection


1. CHECK FUEL TANK VACUUM RELIEF VALVE

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





3.Wipe clean valve housing.





4.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. Refer to "Exploded View" Exploded View.

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