2009 INFINITI QX56 fuel cap

P0455 EVAP CONTROL SYSTEMEC-251
< COMPONENT DIAGNOSIS > [VK56DE]
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Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve
properly.
 If DTC Confirmation Procedure has been previously c onducted, always perform the following before con-
ducting the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
 Perform “DTC WORK SUPPORT” when the fuel level is between 1/4 and 3/4 full, and vehicle is placed
on flat level surface.
 Open engine hood before conducting the following procedures.
WITH CONSULT-III
1. Tighten fuel filler cap securely until ratcheting sound is heard.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
5. Make sure that the following conditions are met.
COOLAN TEMP/S: 0 - 70 °C (32 - 158 °F)
INT/A TEMP SE: 0 - 60 °C (32 - 140 °F)
6. Select “EVP SML LEAK P0442/P1442” of “EVAPO RATIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on the CONSULT-III screen, go to
EC-13, "Basic Inspection"
.
7. Make sure that “OK” is displayed. If “NG” is displayed, select “SELF-DIAG R ESULTS” mode and make sure that “EVAP GROSS LEAK
[P0455]” is displayed. If it is displayed, refer to EC-251, "Diagnosis Procedure"
.
If P0442 is displayed, perform Diagnostic Procedure for DTC P0442, EC-216, "Diagnosis Procedure"
.
WITH GST
NOTE:
Be sure to read the explanation of EC-456, "DTC Index"
before driving vehicle.
1. Start engine.
2. Drive vehicle according to EC-456, "DTC Index"
.
3. Stop vehicle.
4. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
5. Select Service $07 with GST.  If P0441 is displayed on the screen, go to EC-211, "Diagnosis Procedure"
.
 If P0442 is displayed on the screen, go to EC-216, "Diagnosis Procedure"
.
 If P0455 is displayed on the screen, go to EC-251, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771522
1.CHECK FUEL FILLER CAP DESIGN
1. Turn ignition switch OFF.
Revision: December 20092009 QX56

EC-252
< COMPONENT DIAGNOSIS >[VK56DE]
P0455 EVAP CONTROL SYSTEM
2. Check for genuine NISSAN fuel filler cap design.
OK or NG
OK >> GO TO 2.
NG >> Replace with genuine NISSAN fuel filler cap.
2.CHECK FUEL FILLER CAP INSTALLATION
Check that the cap is tightened proper ly by rotating the cap clockwise.
OK or NG
OK >> GO TO 3.
NG >> 1. Open fuel filler cap, then clean cap and fuel filler neck threads using air blower.
2. Retighten until ratcheting sound is heard.
3.CHECK FUEL FILLER CAP FUNCTION
Check for air releasing sound while opening the fuel filler cap.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-264, "Component Inspection"
.
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
5.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks, improper connection or
disconnection.
Refer to EC-37, "Description"
.
OK or NG
OK >> GO TO 6.
NG >> Repair or reconnect the hose.
6.CLEAN EVAP PURGE LINE
Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 7.
7.CHECK EVAP CANISTER VENT CONTROL VALVE
Check the following.
 EVAP canister vent control valve is installed properly. Refer to EC-491, "Removal and Installation"
.
 EVAP canister vent control valve. Refer to EC-232, "Component Inspection"
.
OK or NG
OK >> GO TO 8.
NG >> Repair or replace EVAP cani ster vent control valve and O-ring.
8.INSTALL THE PRESSURE PUMP
SEF915U
Revision: December 20092009 QX56

EC-256
< COMPONENT DIAGNOSIS >[VK56DE]
P0455 EVAP CONTROL SYSTEM
Component Inspection
INFOID:0000000003771523
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
3. If out of specification, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
SEF445Y
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 -
2.90 psi)
Vacuum: −6.0 to −3.3 kPa ( −0.061 to −0.034 kg/cm
2,
− 0.87 to −0.48 psi)
SEF943S
Revision: December 20092009 QX56

P0456 EVAP CONTROL SYSTEMEC-257
< COMPONENT DIAGNOSIS > [VK56DE]
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P0456 EVAP CONTROL SYSTEM
On Board Diagnosis LogicINFOID:0000000003771524
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 vac uum 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 there are no leaks, the diagnosis will be OK.
CAUTION:
 Use only a genuine NISSAN fuel filler cap as a replacemen t. If an incorrect fuel filler cap is used, the
MIL may come on.
 If the fuel filler cap is not tigh tened properly, the MIL may come on.
 Use only a genuine NISSAN rubber tube as a replacement.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0456
0456 Evaporative emission
control system very
small leak (negative
pressure check)  EVAP system has a very small leak.
 EVAP system does not operate prop-
erly.  Incorrect fuel tank vacuum relief valve
 Incorrect fuel filler cap used
 Fuel filler cap remains open or fails to close.
 Foreign matter caught in fuel filler cap.
 Leak is in line between intake manifold and EVAP
canister purge volume control solenoid valve.
 Foreign matter caught in EVAP canister vent con- trol valve.
 EVAP canister or fuel tank leaks
 EVAP purge line (pipe and rubber tube) leaks
 EVAP purge line rubber tube bent
 Loose or disconnected rubber tube
 EVAP canister vent control valve and the circuit
 EVAP canister purge volume control solenoid valve and the circuit
 Fuel tank temperature sensor
 O-ring of EVAP canister vent control valve is miss- ing or damaged
 EVAP canister is saturated with water
 EVAP control system pressure sensor
 Refueling EVAP vapor cut valve
 ORVR system leaks
 Fuel level sensor and the circuit
 Foreign matter caught in EVAP canister purge vol- ume control solenoid valve
PBIB1026E
Revision: December 20092009 QX56

EC-258
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
DTC Confirmation Procedure
INFOID:0000000003771525
NOTE:
 If DTC P0456 is displayed with P0442, firs t perform trouble diagnosis for DTC P0456.
 After repair, make sure that the hoses and clips are installed properly.
 If DTC Confirmation Procedure has been previously conducted, always perform the following before con-
ducting the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
 Open engine hood before conducting following procedure.
 If any of following conditions are met just befo re the DTC confirmation procedure, leave the vehicle
for more than 1 hour.
- Fuel filler cap is removed.
- Fuel is refilled or drained.
- EVAP component parts is/are removed.
 Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Make sure the following conditions are met.
FUEL LEVEL SE: 0.25 - 1.4V
COOLAN TEMP/S: 0 - 32 °C (32 - 90 °F)
FUEL T/TMP SE: 0 - 35 °C (32 - 95 °F)
INT/A TEMP SE: More than 0 °C (32 °F)
If NG, turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle) or refilling/draining
fuel until the output voltage condition of the “FUE L 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, wait at least 10 seconds and then turn ON.
4. Select “EVP V/S LEAK P0456/P1456” of “EVAPO RATIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-III.
Follow the instruction displayed.
5. Make sure that “OK” is displayed. If “NG” is displayed, refer to EC-259, "Diagnosis Procedure"
.
NOTE:
 If the engine speed cannot be maintained with in the range displayed on CONSULT-III screen, go
to EC-13, "Basic Inspection"
.
 Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid
valve properly.
Overall Function CheckINFOID:0000000003771526
WITH GST
Use this procedure to check the overall function of the EV AP very small leak function. During this check, a 1st
trip DTC might not be confirmed.
CAUTION:
 Do not use compressed air, doing so may damage the EVAP system.
 Do not start engine.
 Do not exceeded 4.12 kPa (0.042 kg/cm
2 , 0.6 psi).
Revision: December 20092009 QX56

P0456 EVAP CONTROL SYSTEMEC-259
< COMPONENT DIAGNOSIS > [VK56DE]
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1. Attach the EVAP service port
adapter (commercial service tool)
securely to the EVAP service port.
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 EV AP canister vent control valve
(close).
7. Apply pressure and make sure the following conditions are sat- isfied.
Pressure to be applied: 2.7 kPa (20 mmHg, 0.79 inHg)
Time to be waited after the pressure drawn in to the EVAP
system and the pressure to be dropped: 60 seconds and
the pressure should not be dr opped more than 0.4 kPa (3
mmHg, 0.12 inHg).
If NG, go to EC-259, "Diagnosis Procedure"
.
If OK, go to next step.
8. Disconnect GST.
9. Start engine and warm it up to normal operating temperature.
10. Turn ignition switch OFF and wait at least 10 seconds.
11. Restart engine and let it idle for 90 seconds.
12. Keep engine speed at 2,000 rpm for 30 seconds.
13. Turn ignition switch OFF. NOTE:
For more information, refe r to GST Instruction Manual.
Diagnosis ProcedureINFOID:0000000003771527
1.CHECK FUEL FILLER CAP DESIGN
1. Turn ignition switch OFF.
2. Check for genuine NISSAN fuel filler cap design.
OK or NG
OK >> GO TO 2.
NG >> 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.
OK or NG
OK >> GO TO 3.
NG >> 1. Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. 2. Retighten until ratcheting sound is heard.
BBIA0366E
SEF462UI
SEF915U
Revision: December 20092009 QX56

EC-260
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
3.CHECK FUEL FILLER CAP FUNCTION
Check for air releasing sound while opening the fuel filler cap.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-264, "Component Inspection"
.
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
5.INSTALL THE PRESSURE PUMP
To locate the EVAP leak, install EVAP service port adapter and pres-
sure pump to EVAP service port securely.
NOTE:
Improper installation of the EV AP service port adapter to the
EVAP service port may cause leaking.
With CONSULT-III>>GO TO 6.
Without CONSULT-III>>GO TO 7.
6.CHECK FOR EVAP LEAK
With CONSULT-III
1. Turn ignition switch ON.
2. Select “EVAP SYSTEM CLOSE” of “WORK SUPPORT” mode with CONSULT-III.
3. Touch “START” and apply pressure into the EVAP line until the pressure indicator reaches the middle of
the bar graph.
CAUTION:
 Do not use compressed air or a high pressure pump.
 Do not exceed 4.12 kPa (0.042 kg/cm
2 , 0.6 psi) of pressure in the system.
BBIA0366E
SEF916U
Revision: December 20092009 QX56

EC-264
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
NG >> Replace fuel level sensor unit.
24.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771528
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
3. If out of specification, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
SEF445Y
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 -
2.90 psi)
Vacuum: −6.0 to −3.3 kPa ( −0.061 to −0.034 kg/cm
2,
− 0.87 to −0.48 psi)
SEF943S
Revision: December 20092009 QX56