2011 INFINITI QX56 stop start

EC-308
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0420, P0430 THREE
WAY CATALYST FUNCTION
3.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Wait 5 seconds at idle.
2. Rev engine between 2,000 and 3,000 rpm and maintain it until “INCMP” of “CATALYST” changes to “CMPLT” (It will take approximately 5 minutes).
Does the indication change to
“CMPLT”?
YES >> GO TO 5.
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE AGAIN
1. Stop engine and cool it down to less than 70 °C (158 °F).
2. Perform DTC CONFIRMATION PROCEDURE again.
>> GO TO 2.
5.PERFORM DTC CONFIRMATION PROCEDURE-III
Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-309, "Diagnosis Procedure".
NO >> INSPECTION END
6.PERFORM COMPONENT FUNCTION CHECK
WITH GST
Perform component function check. Refer to EC-308, "
Component Function Check".
NOTE:
Use component function check to check the overall functi on of the three way catalyst (manifold). During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-309, "
Diagnosis Procedure"
Component Function CheckINFOID:0000000006217852
1.PERFORM COMPONENT FUNCTION CHECK
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Open engine hood.
6. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-309, "
Diagnosis Procedure".
DTC ECM
Condition Voltage
Connector +–
Terminal Terminal
P0420 F110 96
[HO2S2
(bank 1)] 100Keeping engine speed at 2,500 rpm
constant under no load The voltage fluctuation cycle takes more
than 5 seconds.
 1 cycle: 0.6 - 1.0
→ 0 - 0.3 → 0.6 - 1.0
P0430 87
[HO2S2
(bank 2)]
Revision: 2010 May2011 QX56

EC-314
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0441 EVAP CONTROL SYSTEM
5. Set voltmeter probes to ECM harness connector terminals under the following conditions.
6. Check EVAP control system pressure sensor value at idle speed and note it.
7. Establish and maintain the following conditions for at least 1 minute.
8. Verify that EVAP control system pressure sensor
value stays 0.1 V less than the value at idle speed (mea-
sured at step 6) for at least 1 second.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to EC-314, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006288306
1.CHECK EVAP CANISTER
1. Turn ignition switch OFF.
2. Check EVAP canister for cracks.
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 2.
YES-2 >> Without CONSULT-III: GO TO 3.
NO >> Replace EVAP canister. Refer to FL-12, "
Removal and Installation".
2.CHECK PURGE FLOW
WITH CONSULT-III
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser-
vice port.
2. Start engine and let it idle.
3. Select “PURG VOL CONT/V” in “A CTIVE TEST” mode with CONSULT-III.
4. Touch “Qd” and “Qu” on CONSULT-III screen to adjust “PURG VOL CONT/V” opening and check vacuum
existence.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 4.
3.CHECK PURGE FLOW
WITHOUT CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser-
vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-45, "
EVAPORATIVE
EMISSION SYSTEM : System Description".
ECM
Connector +–
Te r m i n a l Te r m i n a l
E80 143
(EVAP control system pressure sensor signal) 150
Air conditioner switch ON
Headlamp switch ON
Rear window defogger switch ON
Engine speed Approx. 3,000 rpm
Gear position Any position other than P, N or R
PURG VOL CONT/V Vacuum 100% Existed0% Not existed
Revision: 2010 May2011 QX56

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-317
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0443 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE
DTC LogicINFOID:0000000006288307
DTC DETECTION LOGIC
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:
 Perform “DTC CONFIRMATION PROCEDURE” when the fuel level is between 1/4 and 3/4 full, and
vehicle is placed on flat level surface.
 Always perform test at a temperature of 5 to 60 °C (41 to 140 °F).
 Cool the vehicle so that engi ne coolant temperature becomes same level as ambient temperature.
Do you have CONSULT-III
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE A
WITH CONSULT-III
1. Turn ignition switch ON.
2. Check that the following condition are met. FUEL T/TMP SE: 0 - 35 °C (32 - 95 °F)
3. Start engine and wait at least 60 seconds.
4. Check 1st trip DTC.
IS 1st trip DTC detected?
OK >> Proceed to EC-318, "Diagnosis Procedure".
NG >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE B
WITH CONSULT-III
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. Turn ignition switch ON.
6. Select “PURG VOL CN/V P1444” of “EVAPORA TIVE SYSTEM” in “DTC WORK SUPPORT” mode with
CONSULT-III.
7. Touch “START”.
8. Start engine and let it idle until “TESTING” on CO NSULT-III changes to “COMPLETED”. (It will take
approximately 10 seconds.)
If “TESTING” is not displayed afte r 5 minutes, retry from step 2.
9. Touch “SELF-DIAG RESULTS”.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0443 PURG VOLUME CONT/V
(EVAP canister purge vol-
ume control solenoid valve) A
The canister purge flow is detected dur-
ing the vehicle is stopped while the en-
gine is running, even when EVAP
canister purge volume control solenoid
valve is completely closed.  EVAP control system pressure sensor
 EVAP canister purge volume control
solenoid valve
(The valve is stuck open.)
 EVAP canister vent control valve
 EVAP canister
 Hoses (Hoses are connected incorrectly or
clogged.)
B
The canister purge flow is detected dur-
ing the specified driving conditions, even
when EVAP canister purge volume con-
trol solenoid valve is completely closed.
Revision: 2010 May2011 QX56

P0456 EVAP CONTROL SYSTEMEC-349
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
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

P0507 ISC SYSTEMEC-361
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2.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.
NO >> GO TO 3.
3.REPLACE ECM
1. Stop engine.
2. Replace ECM.
3. Perform additional service when replacing ECM. Refer to EC-143, "
Work Procedure".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-438
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ASCD BRAKE SWITCH
P1572 ASCD BRAKE SWITCH
DTC LogicINFOID:0000000006217943
DTC DETECTION LOGIC
NOTE:

If DTC P1572 is displayed with DTC P0605, first pe rform the trouble diagnosis for DTC P0605. Refer
to EC-376, "
DTC Logic".
 This self-diagnosis has the one tr ip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch is tu rned OFF. And even when malfunction A is detected
in two consecutive trips, DTC is not stored in ECM memory.
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.
NOTE:
The procedure for malfunction B is not described. It ta kes an extremely long time to complete the procedure
for malfunction B. By performing the procedure for malfunc tion A, the condition that causes malfunction B can
be detected.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A
1. Start engine (VDC switch OFF).
2. Press MAIN switch and check that CRUISE indicator is displayed in combination meter.
3. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel s 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.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-439, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
1. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1572 ASCD BRAKE SW
(ASCD brake switch) A)
When the vehicle speed is above 30 km/h
(19 MPH), ON signals from the stop lamp
switch and the ASCD brake switch are
sent to the ECM at the same time.  Harness or connectors
(The stop lamp switch circuit is shorted.)
 Harness or connectors
(The ASCD brake switch circuit is short-
ed.)
 Stop lamp switch
 ASCD brake switch
 Incorrect stop lamp switch installation
 Incorrect ASCD brake switch installation
ECM
B)
ASCD brake switch signal is not sent to
ECM for extremely long time while the ve-
hicle is being driven.
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Revision: 2010 May2011 QX56

P1572 ICC BRAKE SWITCHEC-443
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1572 ICC BRAKE SWITCH
DTC LogicINFOID:0000000006217947
DTC DETECTION LOGIC
NOTE:

If DTC P1572 is displayed with DT C P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-376, "
DTC Logic".
 This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch is tu rned OFF. And even when malfunction A is detected
in two consecutive trips, DTC is not stored in ECM memory.
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.
NOTE:
The procedure for malfunction B is not described. It ta kes an extremely long time to complete the procedure
for malfunction B. By performing the procedure for malf unction A, the condition that causes malfunction B can
be detected.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine (VDC switch OFF).
2. Press MAIN switch and check that CRUISE i ndicator is displayed in combination meter.
3. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel s 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.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-444, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
1. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1572 ASCD BRAKE SW
(ICC brake switch) A)
ON signals from the stop lamp switch
and the ICC brake switch are sent to
ECM at the same time.  Harness or connectors
(The stop lamp switch circuit is shorted.)
 Harness or connectors
(The ICC brake switch circuit is shorted.)
Stop lamp switch
 ICC brake switch
 ICC brake hold relay
 Incorrect stop lamp switch installation
 Incorrect ICC brake switch installation
ECM
B)
ICC brake switch signal is not sent to
ECM for extremely long time while the
vehicle is being driven
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Revision: 2010 May2011 QX56

EM-4
< PRECAUTION >
PRECAUTIONS
If turning the steering wheel is required with the battery disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables.
NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wi ll remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
5. When the repair work is completed, re-connect bot h battery cables. With the brake pedal released, turn
the push-button ignition switch from ACC position to ON position, then to LOCK position. (The steering
wheel will lock when the push-button igniti on switch is turned to LOCK position.)
6. Perform self-diagnosis check of all control units using CONSULT-III.
Precaution for Drain Engine Coolant and Engine OilINFOID:0000000006289509
Drain engine coolant and engine oil when engine is cooled.
Precaution for Disconnecting Fuel PipingINFOID:0000000006289510
 Before starting work, check no fire or sp ark producing items are in the work area.
 Release fuel pressure before disconnecting and disassembly.
 After disconnecting pipes, plug openings to stop fuel leakage.
Precaution for Handling High Pressure Fuel SystemINFOID:0000000006289511
 High pressure fuel system components are betw een high pressure fuel pump and fuel injector.
 Always release fuel pressure and never start the engine when performing removal and installation.
 When removing or installing parts without releasing fuel pressure, fuel may be splashed and, if fuel contacts
skin or eyes, it may cause inflammation.
Precaution for Removal and DisassemblyINFOID:0000000006289512
 When instructed to use SST, use specified tools. Always be careful to work safely, avoid forceful or unin-
structed operations.
 Exercise maximum care to avoid damage to mating or sliding surfaces.
 Cover openings of engine system with tape or the equival ent, if necessary, to seal out foreign materials.
 Mark and arrange disassembly parts in an organi zed way for easy troubleshooting and assembly.
 When loosening nuts and bolts, as a basic rule, star t with the one furthest outside, then the one diagonally
opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be used
where noted in the step.
Precaution for Inspection, Repair and ReplacementINFOID:0000000006289513
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precaution for Assembly and InstallationINFOID:0000000006289514
 Use torque wrench to tighten bolts or nuts to specification.
 When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is specified,
do exactly as specified.
 Replace with new gasket, packing, oil seal or O-ring.
 Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for
any restriction and blockage.
 Dowel pins are used for several parts alignment. When replacing and reassembling parts with dowel pins,
check that dowel pins are installed in the original position.
Revision: 2010 May2011 QX56