sensor 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 >> 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

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

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

P0102, P0103 MAF SENSOREC-205
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*: 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-206
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0106 MANIFOLD ABSOL
UTE PRESSURE SENSOR
P0106 MANIFOLD ABSOLU TE PRESSURE SENSOR
DTC LogicINFOID:0000000006288274
DTC DETECTION LOGIC
NOTE:
If DTC P0106 is displayed with ot her DTC, first perform the trouble diagnosis for other DTC.
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.
If engine will not start or stops soon, wait at leas t 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to normal operating temperature.
3. Accelerate the vehicle from 0 to 88 km/h (0 to 55 MPH) under the following conditions: CAUTION:
Always drive at a safe speed.
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses.
4. Check 1st trip DTC. WITHOUT CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Drive the vehicle under the following conditions.
3. With selector lever in D position, accelerate the v ehicle from 0 to 88 km/h (0 to 55 MPH) under the follow-
ing conditions:
CAUTION:
Always drive at a safe speed.
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0106 ABSL PRES SEN/CIRC
[Manifold absolute pressure (MAP)
circuit range/performance] A difference exceeding the specified
value develops between a value
transmitted from the manifold abso-
lute pressure (MAP) sensor to ECM
and an estimated intake pressure of
intake manifold calculated by ECM.  Harness or connectors
(The manifold absolute pressure
(MAP) sensor circuit is open or
shorted.)
 manifold absolute pressure (MAP)
sensor
 Intake air leaks
ACCEL SEN 1 1.4 – 2.0 V
Selector lever D position
Revision: 2010 May2011 QX56

P0106 MANIFOLD ABSOLUTE PRESSURE SENSOREC-207
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4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to
EC-207, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288275
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 >> Repair or replace malfunctioning part.
2.CHECK MANIFOLD ABSOLUTE PR ESSURE (MAP) SENSOR POWER SUPPLY CIRCUIT FOR OPEN
AND SHORT
1. Disconnect manifold absolute pressu re (MAP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between manifold absolute pr essure (MAP) sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR GR OUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between manifold absolute pressure (MAP) sensor harness connector and ECM har-
ness connector.
4. Also check harness for short to ground and 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 MANIFOLD ABSOLUTE PRESSURE (MAP) SE NSOR INPUT SIGNAL CIRCUIT FOR OPEN AND
SHORT
1. Check the continuity between manifold absolute pressure (MAP) sensor harness connector and ECM har-
ness connector.
Accelerator pedal position sensor 1 Ground Voltage (V)
Connector Terminal
E110 (Without ICC) 3
Ground 1.4 – 2.0
E67 (With ICC) 10
Manifold absolute pressure (MAP) sensor Ground Voltage (V)
Connector Terminal
F65 1 Ground Approx. 5
Manifold absolute pressure (MAP) sensor ECM Continuity
Connector Terminal Connector Terminal
F65 3 F110 70 Existed
Revision: 2010 May2011 QX56

EC-208
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0106 MANIFOLD ABSOL
UTE PRESSURE SENSOR
2. Also check harness for short to ground and power.
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 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
Refer to EC-208, "
Component Inspection (MAP Sensor)".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace manifold absolute pr essure (MAP) sensor. Refer to EM-30, "
Exploded View".
6.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspecti on (MAP Sensor)INFOID:0000000006288276
1.CHECK MAP SENSOR-I
1. Turn ignition switch OFF.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
4. Check the voltage between ECM harness connector terminals as follows.
NOTE:
 To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine
is stopped.
 Because the sensor is absolute pressure sens or, output value may differ depending on atmospheric
pressure and altitude.
5. Measure the atmospheric pressure. NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the
pressure with the following chart.
6. Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.
Manifold absolute pressure (MAP) sensor ECM
Continuity
Connector Terminal Connector Terminal
F65 2 F110 67 Existed
ECM
+–
Connector Terminal Connector Terminal F110 67 F110 70
Altitude (m) Compensated pressure (hPa)00
200 -24
400 -47
600 -70
800 -92
1000 -114
1500 -168
2000 -218
Revision: 2010 May2011 QX56

P0106 MANIFOLD ABSOLUTE PRESSURE SENSOREC-209
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Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace MAP sensor.
2.CHECK MAP SENSOR-II
1. Start engine and let it idle.
2. Check intake manifold vacuum.
3. Check the voltage between ECM harness connector terminals as per the following.
4. Confirm the difference of the voltage when engine is stopped and at idling is within the values shown in the following chart.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace MAP sensor.
Atmospheric pressure (hPa) Voltage (V)
800 3.1 – 3.7
850 3.3 – 3.9
900 3.5 – 4.1
950 3.8 – 4.3
1000 4.0 – 4.6
1050 4.2 – 4.8
JMBIA0870GB
ECM
+–
Connector Terminal Connector Terminal F110 67 F110 70
Intake manifold vacuum [kPA (mmHg)] Voltage difference (V) -40 (-300) 1.5 – 2.0
-53.3 (-400) 2.0 – 2.6
-66.7 (-500) 2.6 – 3.2 -80 (-600) 3.2 – 3.8
Revision: 2010 May2011 QX56

EC-210
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P010A MANIFOLD ABSOL
UTE PRESSURE SENSOR
P010A MANIFOLD ABSOLUTE PRESSURE SENSOR
DTC LogicINFOID:0000000006217792
DTC DETECTION LOGIC
NOTE:
If DTC P010A is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-381, "
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 10 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-210, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217793
1.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR POWER SUPPLY CIRCUIT
1. Disconnect manifold absolute pressu re (MAP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between manifold absolute pr essure (MAP) sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
2.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between manifold absolute pressure (MAP) sensor harness connector and ECM har-
ness connector.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P010A ABSL PRES SEN/CIRC
[Manifold absolute pressure (MAP)
sensor circuit]  An excessively low voltage from
the sensor is sent to ECM.
 An excessively high voltage from the sensor is sent to ECM.  Harness or connectors
(Manifold absolute pressure sen-
sor circuit is shorted.)
 Manifold absolute pressure sensor
Manifold absolute pressure (MAP) sensor Ground Voltage (V)
Connector Terminal
F65 1 Ground Approx. 5
Manifold absolute pressure (MAP) sensor ECM Continuity
Connector Terminal Connector Terminal
F65 3 F110 70 Existed
Revision: 2010 May2011 QX56

P010A MANIFOLD ABSOLUTE PRESSURE SENSOREC-211
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4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK MANIFOLD ABSOLUTE PRESSURE (MAP) SE
NSOR INPUT SIGNAL CIRCUIT FOR OPEN AND
SHORT
1. Check the continuity between manifold absolute pressure (MAP) sensor harness connector and ECM har-
ness connector.
2. 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 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
Refer to EC-211, "
Component Inspection (MAP Sensor)".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace manifold absolute pressure (MAP) sensor. Refer to EM-30, "
Exploded View".
5.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (MAP Sensor)INFOID:0000000006288358
1.CHECK MAP SENSOR-I
1. Turn ignition switch OFF.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
4. Check the voltage between ECM harness connector terminals as follows.
NOTE:
 To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engineis stopped.
 Because the sensor is absolute pressure sens or, output value may differ depending on atmospheric
pressure and altitude.
5. Measure the atmospheric pressure. NOTE:
As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the
pressure with the following chart.
Manifold absolute pressure (MAP) sensor ECM Continuity
Connector Terminal Connector Terminal
F65 2 F110 67 Existed
ECM
+–
Connector Terminal Connector Terminal F110 67 F110 70
Altitude (m) Compensated pressure (hPa)00
200 -24
Revision: 2010 May2011 QX56