2011 INFINITI QX56 sensor

P0456 EVAP CONTROL SYSTEMEC-349
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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9.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. Refer to FL-10, "
Hydraulic Layout".
10.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 and let it idle.
3. Select “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.
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-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.
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 FL-10, "
Hydraulic Layout".
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 EC-320, "
Component Inspection (EVAP Canister Purge Volume Control Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 14.
NO >> Replace EVAP canister purge volume control solenoid valve. Refer to FL-10, "
Exploded View".
14.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-273, "
Component Inspection (Fuel Tank Temperature Sensor)".
Is the inspection result normal?
YES >> GO TO 15.
NO >> Replace fuel level sensor unit. Refer to FL-5, "
Removal and Installation".
15.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-335, "
Component Inspection (EVAP Control System Pressure Sensor)".
Is the inspection result normal?
YES >> GO TO 16. Vacuum should exist.
Vacuum should exist.
Revision: 2010 May2011 QX56

EC-350
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0456 EVAP CONTROL SYSTEM
NO >> Replace EVAP control system pressure sensor. Refer to
EC-335, "Component Inspection (EVAP
Control System Pressure Sensor)".
16.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to FL-10, "
Hydraulic Layout".
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, kink, looseness and improper con-
nection. For location, refer to FL-10, "
Hydraulic Layout".
Is the inspection result normal?
YES >> GO TO 19.
NO >> Repair or replace hoses and tubes.
19.CHECK RECIRCULATION LINE
Check recirculation line between fuel filler tube and fuel tank for clogging, kink, cracks, looseness and
improper connection.
Is the inspection result normal?
YES >> GO TO 20.
NO >> Repair or replace hose, tube or fuel filler tube. Refer to FL-8, "
Exploded View".
20.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-518, "
Component Inspection (EVAP Vapor Cut Valve)".
Is the inspection result normal?
YES >> GO TO 21.
NO >> Replace refueling EVAP vapor cut valve with fuel tank. Refer to FL-10, "
Exploded View".
21.CHECK FUEL LEVEL SENSOR
Refer to MWI-70, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 22.
NO >> Replace fuel level sensor unit. Refer to FL-5, "
Removal and Installation".
22.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Fuel Filler Cap)INFOID:0000000006288327
1.CHECK FUEL FILLER CAP
1. Turn ignition switch OFF.
2. Remove fuel filler cap.
Revision: 2010 May2011 QX56

EC-352
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0460 FUEL LEVEL SENSOR
P0460 FUEL LEVEL SENSOR
DTC LogicINFOID:0000000006288328
DTC DETECTION LOGIC
NOTE:

If DTC P0460 is displayed with DTC UXXXX, first perform the tr ouble diagnosis for DTC UXXXX.
 If DTC P0460 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-378, "
DTC Logic".
When the vehicle is parked, the fuel level in the fuel tank is naturally 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 PROCEDURE
1.PRECONDITIONING
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and wait maximum of 2 consecutive minutes.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-352, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288329
1.CHECK DTC WITH “COMBINATION METER”
Refer to MWI-30, "
CONSULT-III Function".
Is any DTC detected?
YES >> Perform trouble diagnosis of detected DTC.
NO >> GO TO 2.
2.CHECK FUEL LEVEL SENSOR SIGNAL CIRCUIT
Check fuel level sensor signal circuit. Refer to MWI-69, "
Component Function Check".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Perform trouble diagnosis of fuel level sensor signal circuit. Refer to MWI-69,
"DiagnosisProcedure".
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0460 FUEL LEV SEN SLOSH
(Fuel level sensor circuit
noise) Even though the vehicle is parked, a
signal being 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: 2010 May2011 QX56

P0461 FUEL LEVEL SENSOREC-353
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0461 FUEL LEVEL SENSOR
DTC LogicINFOID:0000000006288330
DTC DETECTION LOGIC
NOTE:

If DTC P0461 is displayed with DTC UXXXX, first perform the tr ouble diagnosis for DTC UXXXX.
 If DTC P0461 is displayed with DT C P0607, first perform the trouble diagnosis for DTC P0607. Refer
to EC-378, "
DTC Logic".
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.
DTC CONFIRMATION PROCEDURE
1.PERFORM COMPONENT FUNCTION CHECK
Perform Component Function Check. Refer to EC-353, "
Component Function Check".
Use component function check to check the overall function of the fuel level sensor. During this check, a 1st
trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to EC-354, "
Diagnosis Procedure".
Component Function CheckINFOID:0000000006288331
1.PRECONDITIONING
WARNING:
When performing the following procedure, alw ays observe the handling of the fuel. Refer to FL-2,
"General Precautions".
TESTING CONDITION:
Before starting component function check, preparation of draining fuel and refilling fuel is required.
>> GO TO 2.
2.PERFORM COMPONENT FUNCTION CHECK
NOTE:
Start from step 8, 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-153, "
Work Procedure".
3. Remove the fuel feed hose on the fuel level sensor unit. Refer to FL-5, "
Removal and Installation".
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch ON.
6. Drain fuel by 30 (7-7/8 US gal, 6-5/8 Imp gal) from the fuel tank using proper equipment.
7. Confirm that the fuel gauge indication varies.
8. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
9. Confirm that the fuel gauge indication varies.
Is the inspection result normal?
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0461 FUEL LEVEL SENSOR
(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 distance.  Harness or connectors
(The CAN communication line is open or short-
ed)
 Harness or connectors (The sensor circuit is open or shorted)
 Combination meter
 Fuel level sensor
Revision: 2010 May2011 QX56

EC-354
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0461 FUEL LEVEL SENSOR
YES >> INSPECTION END
NO >> Proceed to
EC-354, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006288332
1.CHECK DTC WITH “COMBINATION METER”
Refer to MWI-30, "
CONSULT-III Function".
Is any DTC detected?
YES >> Perform trouble diagnosis of detected DTC.
NO >> GO TO 2.
2.CHECK FUEL LEVEL SENSOR SIGNAL CIRCUIT
Check fuel level sensor signal circuit. Refer to MWI-69, "
Component Function Check".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Perform trouble diagnosis of fuel level sensor signal circuit. Refer to MWI-69,
"DiagnosisProcedure".
Revision: 2010 May2011 QX56

P0462, P0463 FUEL LEVEL SENSOR
EC-355
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0462, P0463 FUEL LEVEL SENSOR
DTC LogicINFOID:0000000006288333
DTC DETECTION LOGIC
NOTE:

If DTC P0462 or P0463 is displayed with DTC UXXXX, first perform the trouble diagnosis for DTC
UXXXX.
 If DTC P0462 or P0463 is displayed with DTC P0607, first perform the trouble diagnosis for DTC
P0607.Refer to EC-378, "
DTC Logic".
This diagnosis indicates the former, to detect open or short circuit malfunction.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at ignition
switch ON.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-355, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288334
1.CHECK DTC WITH “COMBINATION METER”
Refer to MWI-30, "
CONSULT-III Function".
Is any DTC detected?
YES >> Perform trouble diagnosis of detected DTC.
NO >> GO TO 2.
2.CHECK FUEL LEVEL SENSOR SIGNAL CIRCUIT
Check fuel level sensor signal circuit. Refer to MWI-69, "
Component Function Check".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Perform trouble diagnosis of fuel level sensor signal circuit. Refer to MWI-69,
"DiagnosisProcedure".
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0462 FUEL LEVL SEN/CIRC
(Fuel level sensor circuit low
input) An excessively low voltage from the
sensor is sent 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
P0463 FUEL LEVL SEN/CIRC
(Fuel level sensor circuit high
input) An excessively high voltage from
the sensor is sent to ECM.
Revision: 2010 May2011 QX56

EC-356
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0500 VSS
P0500 VSS
DescriptionINFOID:0000000006217857
The vehicle speed signal is sent to the “combination me
ter” from the “ABS actuator and electric unit (control
unit)” by CAN communication line. The “combination meter” then sends a signal to the ECM by CAN commu-
nication line.
DTC LogicINFOID:0000000006217858
DTC DETECTION LOGIC
NOTE:
 If DTC P0500 is displayed with DTC UXXXX, first perform the tr ouble diagnosis for DTC UXXXX.
 If DTC P0500 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-378, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
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.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK VEHICLE SPEED SIGNAL
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a
road test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Start engine (VDC switch OFF).
2. Read “VHCL SPEED SE” in “DATA MONITOR” mode with CONSULT-III.
The vehicle speed on CONSULT-III should exceed 10 km/h (6 MPH) when rotating wheels with suitable
gear position.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Go to EC-357, "
Diagnosis Procedure".
3.PERFORM DTC CONFIRMATION PROCEDURE
1. Select “DATA MONITOR” mode with CONSULT-III.
2. Warm engine up to normal operating temperature.
3. Maintain the following conditions for at least 50 consecutive seconds. CAUTION:
Always drive vehicle at a safe speed.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0500 VEH SPEED SEN/CIRC
(Vehicle speed sensor) The vehicle speed signal sent to
E C M i s a l m o s t 0 k m / h ( 0 M P H ) e v e n
when vehicle is being driven.  Harness or connectors
(The CAN communication line is open or shorted)
 Harness or connectors (The vehicle speed signal circuit is open or shorted)
 Wheel sensor
 Combination meter
 ABS actuator and electric unit (control unit)
ENG SPEED More than 1,500 rpm
COOLAN TEMP/S More than 70 °C (158 °F)
Revision: 2010 May2011 QX56

EC-358
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0506 ISC SYSTEM
P0506 ISC SYSTEM
DescriptionINFOID:0000000006217861
The ECM controls the engine idle speed to a specified leve
l through the fine adjustment of the air, which is let
into the intake manifold, by operating the electric thrott le control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idli ng speed. The crankshaft position sensor detects the
actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value
memorized in the ECM. The target engine speed is t he lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration and engine load (air conditioner, power steering and cooling fan
operation, etc.).
DTC LogicINFOID:0000000006217862
DTC DETECTION LOGIC
NOTE:
If DTC P0506 is displayed with ot her DTC, first perform the trouble diagnosis for the other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
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.
If the target idle speed is ou t of the specified value, perform EC-148, "
Work Procedure", before con-
ducting DTC Confirmation Procedure.
TESTING CONDITION:
 Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
 Always perform the test at a temperature above −10 °C (14 °F).
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and run it for at least 1 minute at idle speed.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-358, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217863
1.CHECK INTAKE AIR LEAKAGE
1. Start engine and let it idle.
2. Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Discover air leakage location and repair.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0506 ISC SYSTEM
(Idle speed control system
RPM lower than expected) The idle speed is less than the target idle
speed by 100 rpm or more.
 Electric throttle control actuator
 Intake air leakage
Revision: 2010 May2011 QX56