ignition INFINITI QX56 2011 Factory Service Manual
[x] Cancel search | Manufacturer: INFINITI, Model Year: 2011, Model line: QX56, Model: INFINITI QX56 2011Pages: 5598, PDF Size: 94.53 MB
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![INFINITI QX56 2011 Factory Service Manual
P0075, P0081 IVT CONTROL SOLENOID VALVE
EC-193
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P0075, P0081 IVT CONTRO
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DTC LogicINFOID:0000000006217781
DTC DETECTI](/img/42/57033/w960_57033-2216.png "INFINITI QX56 2011 Factory Service Manual
P0075, P0081 IVT CONTROL SOLENOID VALVE
EC-193
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P0075, P0081 IVT CONTRO
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DTC LogicINFOID:0000000006217781
DTC DETECTI")
P0075, P0081 IVT CONTROL SOLENOID VALVE
EC-193
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P0075, P0081 IVT CONTRO
L SOLENOID VALVE
DTC LogicINFOID:0000000006217781
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-193, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217782
1.CHECK INTAKE VALVE TIMING CONTROL SO LENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect intake valve timing (IVT) control solenoid valve harness connector.
3. Turn ignition switch ON.
4. Check the voltage between IVT control solenoid valve harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between IVT control solenoid valve and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK IVT CONTROL SOLENOID VALVE OUTP UT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0075 INT/V TIM V/CIR-B1
[Intake valve timing control sole-
noid valve (bank 1) circuit]
An improper voltage is sent to the ECM
through intake valve timing control solenoid
valve. Harness or connectors
(Intake valve timing control solenoid
valve circuit is open or shorted.)
Intake valve timing control solenoid valve
P0081 INT/V TIM V/CIR-B2
[Intake valve timing control sole-
noid valve (bank 2) circuit]
DTC
IVT control solenoid valve
Ground Voltage
Bank Connector Terminal
P0075 1 F47 2 Ground Battery voltage
P0081 2 F61 2
Revision: 2010 May2011 QX56
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![INFINITI QX56 2011 Factory Service Manual
EC-194
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0075, P0081 IVT CONTROL SOLENOID VALVE
2. Disconnect ECM harness connector.
3. Check the continuity between IVT control sol
enoid valve harness connector and](/img/42/57033/w960_57033-2217.png "INFINITI QX56 2011 Factory Service Manual
EC-194
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0075, P0081 IVT CONTROL SOLENOID VALVE
2. Disconnect ECM harness connector.
3. Check the continuity between IVT control sol
enoid valve harness connector and")
EC-194
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P0075, P0081 IVT CONTROL SOLENOID VALVE
2. Disconnect ECM harness connector.
3. Check the continuity between IVT control sol
enoid valve harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK IVT CONTROL SOLENOID VALVE
Refer to EC-194, "
Component Inspection (Intake Valve Timing Control Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace malfunctioning IVT control solenoid valve. Refer to EM-61, "
Exploded View".
5.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Intake Valv e Timing Control Solenoid Valve)INFOID:0000000006288359
1.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-I
1. Turn ignition switch OFF.
2. Disconnect intake valve timing control solenoid valve harness connector.
3. Check resistance between intake valve timing control solenoid valve terminals as per the following.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace malfunctioning intake valve timing control solenoid valve. Refer to EM-61, "
Exploded
View".
2.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE-II
1. Remove intake valve timing control solenoid valve.
2. Provide 12 V DC between intake valve timing control solenoid valve terminals 1 and 2, and then interrupt it. Check that the
plunger moves as shown in the figure.
CAUTION:
Never apply 12 V DC continuously for 5 seconds or more.
Doing so may result in damage to the coil in intake valve
timing control solenoid valve.
NOTE:
Always replace O-ring when intake valve timing control
solenoid valve is removed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning intake valve timing control solenoid valve. Refer to EM-61, "
Exploded
View".
DTCIVT control solenoid valve ECM
Continuity
Bank Connector Terminal Connector Terminal
P0075 1 F47 1 F 11149
Existed
P0081 2 F61 1 54
Terminals Resistance
1 and 2 7.0 - 7.7 Ω [at 20 °C (68 °F)]
1 or 2 and ground ∞
Ω
(Continuity should not exist)
JMBIA0079ZZ
Revision: 2010 May2011 QX56
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![INFINITI QX56 2011 Factory Service Manual
P0087, P0088, P0090 FRP CONTROL SYSTEM
EC-195
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P0087, P0088, P0090 FRP CONTROL SYSTEM
DTC LogicINFOID:0000000006217784
DTC DETECTION](/img/42/57033/w960_57033-2218.png "INFINITI QX56 2011 Factory Service Manual
P0087, P0088, P0090 FRP CONTROL SYSTEM
EC-195
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P0087, P0088, P0090 FRP CONTROL SYSTEM
DTC LogicINFOID:0000000006217784
DTC DETECTION")
P0087, P0088, P0090 FRP CONTROL SYSTEM
EC-195
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P0087, P0088, P0090 FRP CONTROL SYSTEM
DTC LogicINFOID:0000000006217784
DTC DETECTION LOGIC
NOTE:
If DTC P0087 or P0090 is displayed with DTC P1197, first perform the trouble diagnosis for DTC
P1197.
DTC P0087 or P0090 may be displayed when running out of gas.
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-I
1. Check that the fuel tank is 1/8 full of fuel.
2. Warm up the engine to the normal operating temperature and keep the engine speed at idle for 60 sec- onds.
NOTE:
Warm up the engine until “COOLAN TEMP/S” on “DATA MONITOR” of CONSULT-III reaches at least
70 °C (158 °F).
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-196, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Cool the engine until the engine coolant temperature reaches 60 °C (140 °F) or less.
2. Start the engine and wait at least 60 seconds.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-196, "Diagnosis Procedure".
NO >> INSPECTION END
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0087 High fuel pressure too low The following condition continues for 5
seconds or more after engine start (re-
gardless of water temperature): Target
fuel pressure
− Actual fuel pressure ≥
2.7 MPa (27 bar, 27.5 kg/cm
2, 392 psi)
Harness or connectors(The fuel pump circuit is open or shorted.)
Fuel system
P0088 high fuel pressure too high The following condition continues for 5
seconds or more after engine start (re-
gardless of water temperature):Actual
fuel pressure
− Target fuel pressure ≥
2.7 MPa (27 bar, 27.5 kg/cm
2, 392 psi)
P0090 High pressure fuel pump per-
formance Fuel rail pressure remains at 1.5 MPa
(15 bar, 15.3 kg/ cm
2, 217.5 psi) or less
for 3 seconds or more during engine rev.
Revision: 2010 May2011 QX56
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![INFINITI QX56 2011 Factory Service Manual
EC-196
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0087, P0088, P009
0 FRP CONTROL SYSTEM
Diagnosis Procedure
INFOID:0000000006217785
1.CHECK LOW FUEL PRESSURE
WITH CONSULT-III
1. Start the engine.
2. Check](/img/42/57033/w960_57033-2219.png "INFINITI QX56 2011 Factory Service Manual
EC-196
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P0087, P0088, P009
0 FRP CONTROL SYSTEM
Diagnosis Procedure
INFOID:0000000006217785
1.CHECK LOW FUEL PRESSURE
WITH CONSULT-III
1. Start the engine.
2. Check")
EC-196
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P0087, P0088, P009
0 FRP CONTROL SYSTEM
Diagnosis Procedure
INFOID:0000000006217785
1.CHECK LOW FUEL PRESSURE
WITH CONSULT-III
1. Start the engine.
2. Check “L/FUEL PRES SEN V” in “DAT A MONITOR” of “ECM” with CONSULT-III.
WITHOUT CONSULT-III
1. Start the engine.
2. Check low fuel pressure sensor signal voltage.
Is inspection result normal?
YES >> GO TO 2.
NO >> Check low fuel pressure system. Refer to EC-512, "
Diagnosis Procedure".
2.PERFORM THE HIGH PRESSURE FUEL PUMP COMPONENT INSPECTION
Perform the high pressure fuel pum p component inspection. Refer to EC-196, "
Component Inspection".
Is inspection result normal?
YES >> GO TO 3.
NO >> Replace the fuel pump.
3.CHECK FUEL LEAKAGE
1. Start the engine.
2. Visually check that the fuel pump, fuel rail, and fuel piping have no fuel leakage.
Is inspection result normal?
YES >> Check that the fuel syst em has no breakage, bend, and crush.
NO >> Repair or Replace the error-detected parts.
Component InspectionINFOID:0000000006217786
1.CHECK HIGH PRESSURE FUEL PUMP-I
1. Turn ignition switch OFF.
2. Disconnect high pressure fuel pump harness connector.
3. Check the resistance between high pressure fuel pump terminals as follows.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace high pressure fuel pump. Refer to EM-49, "
Removal and Installation".
Data monitor item Condition Va l u e
(Approx.)
L/FUEL PRES SEN V Engine speed: idle
3,000 –3,300 mV
Engine speed: 3,000 rpm (no load)
+ −Condition Va l u e
(Approx.)
Low fuel pressure sensor
Connector Terminal
F25 2 Ground Engine speed: idle
3.0 –3.3 V
Engine speed: 3,000 rpm (no load)
+ −
Condition Resistance
High pressure fuel pump
Te r m i n a l
1 2 Temperature °C ( °F) 20 – 30 (68 - 86) 9 - 11 Ω
Revision: 2010 May2011 QX56
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EC-198
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P008A LOW FUEL PRESSURE CONTROL SYSTEM
P008A LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006217787
DTC DETECTION LOGIC
NOTE:
If DTC P008A is displ](/img/42/57033/w960_57033-2221.png "INFINITI QX56 2011 Factory Service Manual
EC-198
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P008A LOW FUEL PRESSURE CONTROL SYSTEM
P008A LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006217787
DTC DETECTION LOGIC
NOTE:
If DTC P008A is displ")
EC-198
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P008A LOW FUEL PRESSURE CONTROL SYSTEM
P008A LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006217787
DTC DETECTION LOGIC
NOTE:
If DTC P008A is displayed with DTC P1197, first pe
rform the trouble diagnosis for DTC P1197. Refer to
EC-397, "
DTC 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:
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. Check that the fuel tank is 1/8 full of fuel.
2. Start the engine and warm it up to the normal operating temperature. NOTE:
When replacing ECM, warm up the engine until “C OOLAN TEMP/S” on “DATA MONITOR” of CONSULT-
III reaches at least 70 °C (158 °F).
3. Let the engine at idle for 60 seconds.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-398, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217788
1.PERFORM LOW PRESSURE FUEL PUMP COMPONENT FUNCTION CHECK
Refer to EC-512, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform low pressure fuel pump diagnosis. Refer to EC-512, "
Diagnosis Procedure".
2.CHECK FUEL LEAKAGE
1. Start the engine.
2. Visually check that the low fuel pressure system has no fuel leakage.
Is inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK LOW PRESSURE FUEL PIPING AND HOSE
1. Turn ignition switch OFF.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P008A Low fuel pressure too low A condition of low fuel pressure 0.23
MPa (2.3 bar, 2.346 kg/cm
2, 33.35 psi)
or less continues for 5 seconds or more
after warming up the engine. Harness or connectors
(The low pressure fuel pump circuit is
open or shorted.)
Low pressure fuel pump
Fuel pressure regulator
Low pressure fuel system
Out of gas
Revision: 2010 May2011 QX56
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EC-200
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P008B LOW FUEL PRESSURE CONTROL SYSTEM
P008B LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006288272
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE](/img/42/57033/w960_57033-2223.png "INFINITI QX56 2011 Factory Service Manual
EC-200
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P008B LOW FUEL PRESSURE CONTROL SYSTEM
P008B LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006288272
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE")
EC-200
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P008B LOW FUEL PRESSURE CONTROL SYSTEM
P008B LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006288272
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
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. Start the engine and keep the engine speed at idle for 60 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-200, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288273
1.CHECK FUEL PUMP CONTROL MODULE (FPCM) SIGNAL
Refer to EC-405, "
Component Inspection (FPCM)".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace FPCM. Refer to EC-537, "
Removal and Installation".
2.CHECK FUEL PUMP CONTROL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect FPCM harness connector and fuel level sensor unit and fuel pump harness connector.
3. Check the continuity between FPCM harness connecto r and fuel level sensor unit and fuel pump harness
connector.
4. Also check harness for short to ground and short to power.
Is inspection result normal?
YES >> Replace fuel level sensor unit and fuel pump (fuel pressure regulator malfunction). Refer to FL-5,
"Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P008B Low fuel pressure too high A condition of low fuel pressure 0.67
MPa (6.7 bar, 6.834 kg/cm
2, 97.15 psi)
or more continues for 5 seconds or
more after warming up the engine. Harness or connectors
(The low pressure fuel pump circuit is
open or shorted.)
Fuel pressure regulator
FPCM Fuel level sensor unit and fuel pump Continuity
Connector Terminal Connector Terminal
B41 6
C5 3
Existed
71
Revision: 2010 May2011 QX56
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![INFINITI QX56 2011 Factory Service Manual
P0102, P0103 MAF SENSOREC-201
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P0102, P0103 MAF SENSOR
DTC LogicINFOID:0000000006217789
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDUR](/img/42/57033/w960_57033-2224.png "INFINITI QX56 2011 Factory Service Manual
P0102, P0103 MAF SENSOREC-201
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P0102, P0103 MAF SENSOR
DTC LogicINFOID:0000000006217789
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDUR")
P0102, P0103 MAF SENSOREC-201
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P0102, P0103 MAF SENSOR
DTC LogicINFOID:0000000006217789
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0102
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> INSPECTION END
3.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-I
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-II
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217790
1.INSPECTION START
Confirm the detected DTC.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.CHECK INTAKE SYSTEM
Check the following for connection.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0102 MAF SEN/CIRCUIT-B1
(Mass air flow sensor circuit
low input) An excessively low voltage from the sensor is
sent to ECM. Harness or connectors
(The mass air flow sensor circuit is
open or shorted.)
Intake air leakage
Mass air flow sensor
P0103 MAF SEN/CIRCUIT-B1
(Mass air flow sensor circuit
high input) An excessively high voltage from the sensor is
sent to ECM. Harness or connectors
(The mass air flow sensor circuit is
open or shorted.)
Mass air flow sensor
Revision: 2010 May2011 QX56
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EC-202
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
Air duct
Vacuum hoses
Intake air passage between air duct to intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO](/img/42/57033/w960_57033-2225.png "INFINITI QX56 2011 Factory Service Manual
EC-202
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
Air duct
Vacuum hoses
Intake air passage between air duct to intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO")
EC-202
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
Air duct
Vacuum hoses
Intake air passage between air duct to intake manifold
Is the inspection result normal?
YES >> GO TO 3.
NO >> Reconnect the parts.
3.CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between MAF sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness for open or short between mass air flow sensor and ECM
Harness for open or short between mass air flow sensor and IPDM E/R
Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between MAF sens or harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between MAF sens or harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK MASS AIR FLOW SENSOR
Refer to EC-203, "
Component Inspection (MAF Sensor)".
Is the inspection result normal?
MAF sensor Ground Voltage
Connector Terminal
F31 5 Ground Battery voltage
MAF sensor ECM Continuity
Connector Terminal Connector Terminal
F 3 1 4 F 111 2 5 E x i s t e d
MAF sensor ECM Continuity
Connector Terminal Connector Terminal
F 3 1 3 F 111 2 2 E x i s t e d
Revision: 2010 May2011 QX56
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P0102, P0103 MAF SENSOREC-203
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YES >> GO TO 8.
NO >> Replace mass air flow sensor. Refer to
EM-27, "
Exploded View".
8.CHECK INTERMI](/img/42/57033/w960_57033-2226.png "INFINITI QX56 2011 Factory Service Manual
P0102, P0103 MAF SENSOREC-203
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YES >> GO TO 8.
NO >> Replace mass air flow sensor. Refer to
EM-27, \"
Exploded View\".
8.CHECK INTERMI")
P0102, P0103 MAF SENSOREC-203
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YES >> GO TO 8.
NO >> Replace mass air flow sensor. Refer to
EM-27, "
Exploded View".
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (MAF Sensor)INFOID:0000000006290102
1.CHECK MASS AIR FLOW SENSOR-I
WITH CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Start engine and warm it up to normal operating temperature.
4. Connect CONSULT-III and select “DATA MONITOR” mode.
5. Select “MAS A/F SE-B1” , and check the indication.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
WITHOUT CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Start engine and warm it up to normal operating temperature.
4. Check the voltage between ECM harness connector terminals under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.CHECK FOR THE CAUSE OF UNEVEN AIR FL OW THROUGH MASS AIR FLOW SENSOR
1. Turn ignition switch OFF.
2. Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
- Crushed air ducts
- Malfunctioning seal of air cleaner element
- Uneven dirt of air cleaner element
- Improper specification of intake air system parts
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
Monitor item Condition Indication (V)
MAS A/F SE-B1 Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.1
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.4 - 1.9
Idle to about 4,000 rpm 0.9 - 1.1 to Approx. 2.4*
ECM Condition Voltage (V)
Connector +–
Terminal Terminal
F 111 22
(MAF sensor signal) 25Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operat-
ing temperature.)
0.9 - 1.1
2,500 rpm (Engine is warmed-up to normal
operating temperature.) 1.4 - 1.9
Idle to about 4,000 rpm 0.9 - 1.1 to Approx. 2.4*
Revision: 2010 May2011 QX56
Page 2228 of 5598
![INFINITI QX56 2011 Factory Service Manual
EC-204
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
3.CHECK MASS AIR FLOW SENSOR-II
WITH CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal op](/img/42/57033/w960_57033-2227.png "INFINITI QX56 2011 Factory Service Manual
EC-204
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
3.CHECK MASS AIR FLOW SENSOR-II
WITH CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal op")
EC-204
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0102, P0103 MAF SENSOR
3.CHECK MASS AIR FLOW SENSOR-II
WITH CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-III and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1””, and check the indication.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
WITHOUT CONSULT-III
1. Repair or replace malfunctioning part.
2. Start engine and warm it up to normal operating temperature.
3. Check the voltage between ECM harness connector terminals under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 4.
4.CHECK MASS AIR FLOW SENSOR-III
WITH CONSULT-III
1. Turn ignition switch OFF.
2. Disconnect mass air flow sensor harness connector and reconnect it again.
3. Start engine and warm it up to normal operating temperature.
4. Connect CONSULT-III and select “DATA MONITOR” mode.
5. Select “MAS A/F SE-B1”, and check the indication.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
WITHOUT CONSULT-III
1. Turn ignition switch OFF.
2. Disconnect mass air flow sensor harness connector and reconnect it again.
3. Start engine and warm it up to normal operating temperature.
4. Check the voltage between ECM harness connector terminals under the following conditions.
Monitor item Condition Indication (V)
MAS A/F SE-B1 Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.1
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.4 - 1.9
Idle to about 4,000 rpm 0.9 - 1.1 to Approx. 2.4*
ECM
Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
F 111 22
(MAF sensor signal) 25Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operat-
ing temperature.)
0.9 - 1.1
2,500 rpm (Engine is warmed-up to normal
operating temperature.) 1.4 - 1.9
Idle to about 4,000 rpm 0.9 - 1.1 to Approx. 2.4*
Monitor item Condition Indication (V)
MAS A/F SE-B1 Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.1
2,500 rpm (Engine is warmed-up to normal operating temperature.) 1.4 - 1.9
Idle to about 4,000 rpm 0.9 - 1.1 to Approx. 2.4*
Revision: 2010 May2011 QX56