2011 INFINITI QX56 heater

EC-296
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0300, P0301, P0302, P
0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
4. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 16.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
16.CHECK A/F SENSOR 1 HEATER
Refer to EC-182, "
Component Inspection (A/F Sensor 1 Heater)".
Is the inspection result normal?
YES >> GO TO 17.
NO >> Replace malfunctioning A/F sensor 1. Refer to EX-5, "
Exploded View".
17.CHECK MASS AIR FLOW SENSOR
WITH CONSULT-III
Check mass air flow sensor signal in “DATA MONITOR” mode with CONSULT-III.
For specification, refer to EC-538, "
Mass Air Flow Sensor".
WITH GST
Check mass air flow sensor signal in Service $01 with GST.
For specification, refer to EC-538, "
Mass Air Flow Sensor".
Is the measurement value within the specification?
YES >> GO TO 18.
NO >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-201, "
Diagnosis Procedure".
18.CHECK SYMPTOM MATRIX CHART
Check items on the rough idle symptom in EC-524, "
Symptom Table".
Is the inspection result normal?
YES >> GO TO 19.
NO >> Repair or replace malfunctioning part.
19.ERASE THE 1ST TRIP DTC
Some tests may cause a 1st trip DTC to be set.
Erase the 1st trip DTC from the ECM memo ry after performing the tests. Refer to EC-63, "
CONSULT-III
Function" or EC-60, "On Board Diagnosis Function".
>> GO TO 20.
20.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P0130 1 F67 6 F11094
Existed
P0150 2 F68 6 74
Revision: 2010 May2011 QX56

EC-396
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1148, P1168 CLOSED LOOP CONTROL
P1148, P1168 CLOSED LOOP CONTROL
DTC LogicINFOID:0000000006288347
DTC DETECTION LOGIC
NOTE:
DTC P1148 or P1168 is displayed with DTC for A/F sensor 1.
When the DTC is detected, perform the trouble di
agnosis of DTC corresponding to A/F sensor 1.
Diagnosis ProcedureINFOID:0000000006288348
DTC P1148 or P1168 is displayed with DTC for A/F sensor 1.
When the DTC is detected, perform the trouble diagnosis of DTC corresponding to A/F sensor 1.Refer to EC-
98, "DTC Index".
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1148 CLOSED LOOP-B1
[Closed loop control function
(bank 1)] The closed loop control function for bank 1
does not operate even when vehicle is being
driven in the specified condition.
 Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
 A/F sensor 1
 A/F sensor 1 heater
P1168 CLOSED LOOP-B2
[Closed loop control function
(bank 2)] The closed loop control function for bank 2
does not operate even when vehicle is being
driven in the specified condition.
Revision: 2010 May2011 QX56

P2A00, P2A03 A/F SENSOR 1EC-487
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P2A00, P2A03 A/F SENSOR 1
DTC LogicINFOID:0000000006217987
DTC DETECTION LOGIC
To judge the malfunction, the A/F signal computed by ECM fr
om the A/F sensor 1 signal is monitored so it will
not shift to LEAN side or RICH side.
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 idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
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. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
6. Let engine idle for 1 minute.
7. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-487, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217988
1.RETIGHTEN A/F SENSOR 1
Loosen and retighten the A/F sensor 1. Refer to EX-5, "
Exploded View".
>> GO TO 2.
2.CHECK A/F SENSOR 1 CONNECTOR
1. Disconnect A/F sensor 1 harness connector.
2. Check that water is not inside connectors.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace harness connector.
3.CHECK FOR INTAKE AIR LEAKAGE
1. Reconnect A/F sensor 1 harness connector.
2. Start engine and run it at idle.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P2A00 A/F SENSOR1 (B1)
(Air fuel ratio (A/F) sensor 1 (bank 1)
circuit range/performance)  The output voltage computed by ECM from
the A/F sensor 1 signal shifts to the lean side
for a specified period.
 The A/F signal computed by ECM from the
A/F sensor 1 signal shifts to the rich side for
a specified period.  A/F sensor 1
 A/F sensor 1 heater
 Fuel pressure
 Fuel injector
 Intake air leaks
P2A03 A/F SENSOR1 (B2)
(Air fuel ratio (A/F) sensor 1 (bank 2)
circuit range/performance)
Revision: 2010 May2011 QX56

P2A00, P2A03 A/F SENSOR 1EC-489
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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4. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
8.CHECK A/F SENSOR 1 HEATER
Refer to EC-182, "
Component Inspection (A/F Sensor 1 Heater)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 10.
9.CHECK INTERMITTENT INCIDENT
Perform GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> GO TO 10.
NO >> Repair or replace malfunctioning part.
10.REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace air fuel ratio (A/F) sensor 1. Refer to EX-5, "
Exploded View".
CAUTION:
 Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
 Before installing new A/F senso r, clean exhaust system threads using Oxygen Sensor Thread
Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant
(commercial service tool).
Will CONSULT-III be used?
YES >> GO TO 11.
NO >> GO TO 12.
11 .CONFIRM A/F ADJUSTMENT DATA
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Check that “0.000” is di splayed on CONSULT-III screen.
Is
“0.000” displayed?
YES >> INSPECTION END
NO >> GO TO 12.
12.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
Will CONSULT-III be used?
YES >> GO TO 13.
NO >> INSPECTION END
13.CONFIRM A/F ADJUSTMENT DATA
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Check that “0.000” is di splayed on CONSULT-III screen.
>> INSPECTION END
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P2A00 1 F67 6 F11094
Existed
P2A03 2 F68 6 74
Revision: 2010 May2011 QX56

ELECTRICAL LOAD SIGNALEC-493
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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ELECTRICAL LOAD SIGNAL
DescriptionINFOID:0000000006217994
The electrical load signal (Rear window defogger switch
signal, headlamp switch signal, heater fan switch sig-
nal, etc.) is transferred via the CAN communication line.
Component Function CheckINFOID:0000000006217995
1.CHECK REAR WINDOW DEF OGGER SWITCH FUNCTION
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-III.
3. Select “LOAD SIGNAL” and check indication under the following conditions.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to EC-493, "
Diagnosis Procedure".
2.CHECK LIGHTING SWITCH FUNCTION
Check “LOAD SIGNAL” indication under the following conditions.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Go to EC-493, "
Diagnosis Procedure".
3.CHECK HEATER FAN CONTROL SWITCH FUNCTION
Select “HEATER FAN SW” and check indication under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-493, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006217996
1.INSPECTION START
Confirm the malfunctioning circuit (rear window defogger, headlamp or heater fan). Refer to EC-493, "
Compo-
nent Function Check".
Which circuit is related to the incident?
Rear window defogger>>GO TO 2.
Headlamp>>GO TO 3.
Heater fan>>GO TO 4.
2.CHECK REAR WINDOW DEFOGGER SYSTEM
Refer to DEF-24, "
Work Flow".
Monitor item Condition Indication
LOAD SIGNAL Rear window defogger switch ON ON
OFF OFF
Monitor item Condition Indication
LOAD SIGNAL Lighting switch ON at 2nd position ON
OFF OFF
Monitor item Condition Indication
HEATER FAN SW Heater fan control switch ON ON
OFF OFF
Revision: 2010 May2011 QX56

EC-494
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ELECTRICAL LOAD SIGNAL
>> INSPECTION END
3.CHECK HEADLAMP SYSTEM
Refer to EXL-59, "
Work Flow".
>> INSPECTION END
4.CHECK HEATER FAN CONTROL SYSTEM
Refer to HAC-60, "
Work Flow".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-538
< SERVICE DATA AND SPECIFICATIONS (SDS) [VK56VD]
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Idle SpeedINFOID:0000000006218038
*: Under the following conditions
 A/C switch: OFF
 Electric load: OFF (Lights, heater fan & rear window defogger)
 Steering wheel: Kept in straight-ahead position
Ignition TimingINFOID:0000000006218039
*: Under the following conditions
 A/C switch: OFF
 Electric load: OFF (Lights, heater fan & rear window defogger)
 Steering wheel: Kept in straight-ahead position
Calculated Load ValueINFOID:0000000006218040
Mass Air Flow SensorINFOID:0000000006218041
*: Engine is warmed up to normal operating temperature and running under no load.Condition Specification
No load* (in P or N position) 600 ± 50 rpm
Condition Specification
No load* (in P or N position) 12 ± 2 °BTDC
Condition Specification (U sing CONSULT-III or GST)
At idle 5 – 35%
At 2,500 rpm 5 – 35%
Supply voltageBattery voltage (11 – 14 V)
Output voltage at idle 0.9 – 1.1 V*
Mass air flow (Using CONSULT-III or GST) 1.0 – 5.0 g/s at idle*
7.0 – 20.0 g/s at 2,500 rpm*
Revision: 2010 May2011 QX56

CYLINDER HEADEM-87
< REMOVAL AND INSTALLATION >
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NOTE:
 As for replacement of parts on the intake side as
shown in the exploded view, replace VVEL ladder assem-
bly & cylinder head assembly. (Only valve oil seals are replaceable as a single part.)
 VVEL ladder assembly cannot be replaced as a singl e part, because it is machined together with cylinder
head assembly.
Removal and InstallationINFOID:0000000006289572
REMOVAL
1. Remove the following parts:  Rocker cover and spark plug: Refer to EM-33, "
Exploded View".
 Intake manifold: Refer to EM-30, "
Exploded View".
 Exhaust manifold: Refer to EM-40, "
Exploded View".
 Water inlet and thermostat housing: Refer to CO-20, "
Exploded View".
 Water pipe and heater pipe: Refer to CO-20, "
Exploded View".
 Timing chain: Refer to EM-61, "
Exploded View".
 Camshaft (EXH) and VVEL ladder assembly: Refer to EM-74, "
Exploded View".
2. Remove cylinder head.  Loosen mounting bolts in reverse order as shown in the figure.
 Use TORX socket and power tool.
3. Remove cylinder head gaskets.
4. Remove oil filter (for VVEL ladder asse mbly) from cylinder block, if necessary.
5. Remove valve lifter.  Identify installation positions, and store them without mixing them up.
INSTALLATION
1. Install oil filter (for VVEL l adder assembly) (1) in the direction
shown in the figure, if removed.
 Check that the oil filter does not protrude from the upper sur-
face of cylinder block (2) after installation.
A: Bank 2
B: Bank 1
: Engine front
JPBIA2145ZZ
JPBIA2129ZZ
Revision: 2010 May2011 QX56