sensor INFINITI QX56 2011 Factory Service Manual

EC-188
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P006A, P0101 MAF SENSOR
CAUTION:
Always drive at a safe speed.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-188, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288270
1.CHECK INTAKE SYSTEM
Check the following for connection.
 Air duct
 Vacuum hoses
 Intake air passage between air duct and intake manifold
Is the inspection result normal?
YES >> GO TO 2.
NO >> Reconnect the parts.
2.CHECK MASS AIR FLOW SENS OR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between mass air flow sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.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.
4.CHECK MASS AIR FLOW SENSOR GR OUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between mass air flow sensor harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Accelerator pedal position sensor 1 Ground Voltage (V)
Connector Terminal
E110 (Whthout ICC) 3 Ground 1.4 – 2.0
E67 (With ICC) 10
Mass air flow sensor Ground Voltage
Connector Terminal
F31 5 Ground Battery volt-
age
Mass air flow sensor ECM Continu-
ity
Connec-
tor Te r m i n a l Connec-
tor Te r m i n a l
F 3 1 4 F 111 2 5 E x i s t e d
Revision: 2010 May2011 QX56

P006A, P0101 MAF SENSOREC-189
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK MASS AIR FLOW SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between mass air flow sensor 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 6.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK MANIFOLD ABSO LUTE PRESSURE SENSOR
Check manifold absolute pressure sensor. Refer to EC-208, "
Component Inspection (MAP Sensor)".
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace manifold absolute pressure sensor. Refer to EM-30, "
Removal and Installation".
7.CHECK INTAKE AIR TEMPERATURE SENSOR
Check intake air temperature sensor. Refer to EC-225, "
Component Inspection (Intake Air Temperature Sen-
sor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace mass air flow sensor (with intake air temperature sensor). Refer to EM-27, "
Removal and
Installation".
8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-335, "
Component Inspection (EVAP Control System Pressure Sensor)".
Is the inspection result normal?
YES-1 (Only DTC P006A is detected)>>GO TO 9.
YES-2 (DTC P006A and P0101 are detected)>>GO TO 10.
NO >> Replace EVAP control system pressure sensor. Refer to FL-12, "
Removal and Installation".
9.CHECK MASS AIR FLOW SENSOR
Refer to EC-190, "
Component Inspection (MAF Sensor)".
Is the inspection result normal?
YES >> GO TO 11.
NO >> Replace mass air flow sensor.
10.CHECK MASS AIR FLOW SENSOR
Check mass air flow sensor. Refer to EC-190, "
Component Inspection (MAF Sensor)".
Is the inspection result normal?
YES >> GO TO 11.
NO >> Replace mass air flow sensor. Refer to EM-27, "
Removal and Installation".
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Mass air flow 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

EC-190
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P006A, P0101 MAF SENSOR
Component Inspection (MAF Sensor)
INFOID:0000000006288271
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.
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.
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

P006A, P0101 MAF SENSOREC-191
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
*: 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 har ness 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 har ness 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

EC-192
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P006A, P0101 MAF SENSOR
*: 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 >> Clean or replace malfunctioning mass air flow sensor. Refer to
EM-27, "
Removal and Installation".
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*
Revision: 2010 May2011 QX56

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 “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

P0087, P0088, P0090 FRP CONTROL SYSTEM
EC-197
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2.CHECK HIGH PRESSURE FUEL PUMP-II
WITH CONSULT-III
1. Reconnect high pressure fuel pump harness connector.
2. Start the engine.
3. Check “FUEL PRES SEN” in “DATA MONITOR” of “ECM” with CONSULT-III.
WITHOUT CONSULT-III
1. Start the engine.
2. Check fuel rail pressure sensor signal voltage.
YES >> INSPECTION END
NO >> Replace high pressure fuel pump. Refer to EM-43, "
Removal and Installation".
Data monitor item Condition Vo l ta g e
(Approx.)
FUEL PRES SEN V Engine speed: idle 980 – 1,200 mV
Engine speed: Revving engine from idle to 4,000 rpm quickly 1,100 – 2,900 mV
+ − Condition Va l u e
(Approx.)
Fuel rail pressure sensor
Connector Terminal
F26 2 Ground Engine speed: idle 0.98 – 1.2 V
Engine speed: Revving engine from idle to 4,000 rpm quickly 1.1 – 2.9 V
Revision: 2010 May2011 QX56

P008A LOW FUEL PRESSURE CONTROL SYSTEMEC-199
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Check that the low pressure fuel piping and hose have no breakage, bend, and crush. Refer to
FL-4,
"Inspection".
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.
Revision: 2010 May2011 QX56

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

P0102, P0103 MAF SENSOREC-201
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
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