2008 INFINITI QX56 Fuel sensor

P0455 EVAP CONTROL SYSTEMEC-259
< COMPONENT DIAGNOSIS > [VK56DE]
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P0455 EVAP CONTROL SYSTEM
On Board Diagnosis LogicINFOID:0000000001351630
This diagnosis detects a very large leak (fuel filler cap
fell off etc.) in EVAP system between the fuel tank and
EVAP canister purge volume control solenoid valve.
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 Confirmation ProcedureINFOID:0000000001351631
CAUTION:
Never remove fuel filler cap duri ng the DTC Confirmation Procedure.
NOTE:
PBIB1026E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0455
0455 EVAP control system
gross leak detected EVAP control system has a very large leak
such as fuel filler cap fell off, EVAP control
system does not operate properly. • Fuel filler cap remains open or fails to close.
• Incorrect fuel tank vacuum relief valve
• Incorrect fuel filler cap used
• Foreign matter caught in fuel filler cap.
• Leak is in line between intake manifold and
EVAP canister purge volume control sole-
noid valve.
• Foreign matter caught in EVAP canister vent control 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 cir- cuit
• EVAP canister purge volume control sole- noid valve and the circuit
• Fuel tank temperature sensor
• O-ring of EVAP canister vent control valve is
missing or damaged.
• EVAP control system pressure sensor
• Refueling EVAP vapor cut valve
• ORVR system leaks
Revision: March 2010 2008 QX56

EC-264
< COMPONENT DIAGNOSIS >[VK56DE]
P0455 EVAP CONTROL SYSTEM
OK >> GO TO 16.
NG >> Replace EVAP canister purge volume control solenoid valve.
16.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-190, "
Component Inspection".
OK or NG
OK >> GO TO 17.
NG >> Replace fuel level sensor unit.
17.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR
Refer to EC-248, "
Component Inspection".
OK or NG
OK >> GO TO 18.
NG >> Replace EVAP control system pressure sensor.
18.CHECK EVAP/ORVR LINE
Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper con-
nection. For location, refer to EC-416
.
OK or NG
OK >> GO TO 19.
NG >> Repair or replace hoses and tubes.
19.CHECK RECIRCULATION LINE
Check recirculation line between filler neck tube and f uel tank for clogging, kink, cracks, looseness and
improper connection.
OK or NG
OK >> GO TO 20.
NG >> Repair or replace hose, tube or filler neck tube.
20.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-418, "
Component Inspection".
OK or NG
OK >> GO TO 21.
NG >> Replace refueling EVAP vapor cut valve with fuel tank.
21.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001351637
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
1. Wipe clean valve housing.
SEF445Y
Revision: March 2010 2008 QX56

EC-266
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
P0456 EVAP CONTROL SYSTEM
On Board Diagn
osis LogicINFOID:0000000001351633
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 sm all leak, the very small leak P0456 will be detected.
If ECM judges a leak equivalent to a smal l 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: March 2010 2008 QX56

P0456 EVAP CONTROL SYSTEMEC-271
< COMPONENT DIAGNOSIS > [VK56DE]
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OK (With CONSULT-III)>>GO TO 12.
OK (Without CONSULT-III)>>GO TO 13.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
• EVAP canister for damage
• EVAP hose between EVAP canister and vehi cle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.
12.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
With CONSULT-III
1. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at EVAP service port.
2. Start engine.
3. Perform “PURG VOL CONT/V ” in “ACTIVE TEST” mode.
4. Touch “Qu” on CONSULT-III screen to increase “PURG VOL CONT/V” opening to 100%.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
OK or NG
OK >> GO TO 15.
NG >> GO TO 14.
13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at 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.
OK or NG
OK >> GO TO 16.
NG >> GO TO 14.
14.CHECK VACUUM HOSE
Check vacuum hoses for clogging or disconnection. Refer to EC-37, "
Description".
OK or NG
OK >> GO TO 15.
NG >> Repair or reconnect the hose.
15.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Refer to EC-238, "
Component Inspection".
OK or NG
OK >> GO TO 16.
NG >> Replace EVAP canister purge volume control solenoid valve.
16.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-190, "
Component Inspection" .
OK or NG
OK >> GO TO 17.
NG >> Replace fuel level sensor unit.
17.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-248, "
Component Inspection".
Vacuum should exist.
Vacuum should exist.
Revision: March 2010
2008 QX56

EC-272
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
OK or NG
OK >> GO TO 18.
NG >> Replace EVAP control system pressure sensor.
18.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to EC-37, "
Description".
OK or NG
OK >> GO TO 19.
NG >> Repair or reconnect the hose.
19.CLEAN EVAP PURGE LINE
Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 20.
20.CHECK EVAP/ORVR LINE
Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper con-
nection. For location, refer to EC-416
.
OK or NG
OK >> GO TO 21.
NG >> Repair or replace hoses and tubes.
21.CHECK RECIRCULATION LINE
Check recirculation line between filler neck tube and f uel tank for clogging, kink, cracks, looseness and
improper connection.
OK or NG
OK >> GO TO 22.
NG >> Repair or replace hose, tube or filler neck tube.
22.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-418, "
Component Inspection".
OK or NG
OK >> GO TO 23.
NG >> Replace refueling EVAP vapor cut valve with fuel tank.
23.CHECK FUEL LEVEL SENSOR
Refer to MWI-34, "
Component Inspection".
OK or NG
OK >> GO TO 24.
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:0000000001351638
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
Revision: March 2010 2008 QX56

EC-274
< COMPONENT DIAGNOSIS >[VK56DE]
P0460 FUEL LEVEL SENSOR
P0460 FUEL LEVEL SENSOR
Component DescriptionINFOID:0000000001351639
The fuel level sensor is mounted in the fuel level sensor unit. The
sensor detects a fuel level in the fuel tank and transmits a signal to
the combination meter. The combination meter sends the fuel level
sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is vari-
able resistor. Fuel level sensor output voltage changes depending on
the movement of the fuel mechanical float.
On Board Diagn
osis LogicINFOID:0000000001351640
NOTE:
•If DTC P0460 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P0460 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
When the vehicle is parked, naturally the fuel level in the fuel tank is stable. It means that output signal of the
fuel level sensor does not change. If ECM senses sloshi ng signal from the sensor, fuel level sensor malfunc-
tion is detected.
DTC Confirmation ProcedureINFOID:0000000001351641
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Start engine and wait maximum of 2 consecutive minutes.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-274, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351642
1.CHECK COMBINATION METER FUNCTION
Refer to MWI-5, "
METER SYSTEM : System Description".
OK or NG
OK >> GO TO 2.
NG >> Go to MWI-34, "
Component Inspection".
2.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
BBIA0402E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0460
0460 Fuel level sensor circuit
noise Even though the vehicle is parked, a signal be-
ing varied is sent from the fuel level sensor to
ECM. • Harness or connectors
(The CAN communication line is open or
shorted)
• Harness or connectors
(The sensor circuit is open or shorted)
• Combination meter
• Fuel level sensor
Revision: March 2010 2008 QX56

P0460 FUEL LEVEL SENSOREC-275
< COMPONENT DIAGNOSIS > [VK56DE]
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>>
INSPECTION END
Revision: March 2010 2008 QX56

EC-276
< COMPONENT DIAGNOSIS >[VK56DE]
P0461 FUEL LEVEL SENSOR
P0461 FUEL LEVEL SENSOR
Component DescriptionINFOID:0000000001351644
The fuel level sensor is mounted in the fuel level sensor unit. The
sensor detects a fuel level in the fuel tank and transmits a signal to
the combination meter. The combination meter sends the fuel level
sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is vari-
able resistor. Fuel level sensor output voltage changes depending on
the movement of the fuel mechanical float.
On Board Diagn
osis LogicINFOID:0000000001351645
NOTE:
•If DTC P0461 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P0461 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
Driving long distances naturally affect fuel gauge level.
This diagnosis detects the fuel gauge malfunction of the gauge not moving even after a long distance has
been driven.
Overall Function CheckINFOID:0000000001351646
Use this procedure to check the overall function of the fuel level sensor function. During this check, a 1st trip
DTC might not be confirmed.
WARNING:
When performing following proced ure, be sure to observe the handling of the fuel. Refer to FL-11,
"Removal and Installation".
TESTING CONDITION:
Before starting overall function check, preparation of draining fuel and refi lling fuel is required.
WITH CONSULT-III
NOTE:
Start from step 10, if it is possible to confirm that the fuel cannot be drained by 30 (7-7/8 US gal, 6-5/
8 Imp gal) in advance.
1. Prepare a fuel container and a spare hose.
2. Release fuel pressure from fuel line, refer to EC-494, "
Fuel Pressure Check".
3. Remove the fuel feed hose on the fuel level sensor unit.
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch OFF and wait at least 10 seconds then turn ON.
6. Select “FUEL LEVEL SE” in “DAT A MONITOR” mode with CONSULT-III.
7. Check “FUEL LEVEL SE” output voltage and note it.
8. Select “FUEL PUMP” in “ACTIVE TEST” mode with CONSULT-III.
9. Touch “ON” and drain fuel approximately 30 (7-7/8 US gal, 6-5/8 Imp gal) and stop it.
10. Check “FUEL LEVEL SE” output voltage and note it.
11. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
BBIA0402E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0461
0461 Fuel level sensor circuit
range/performance The output signal of the fuel level sensor does
not change within the specified range even
though the vehicle has been driven a long dis-
tance. • Harness or connectors
(The CAN communication line is open or
shorted)
• Harness or connectors
(The sensor circuit is open or shorted)
• Combination meter
• Fuel level sensor
Revision: March 2010 2008 QX56