sensor INFINITI QX56 2009 Factory Service Manual

EC-74
< COMPONENT DIAGNOSIS >[VK56DE]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
COMPONENT DIAGNOSIS
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
DescriptionINFOID:0000000003771320
The specification (SP) value indicates the tolerance of
the value that is displayed in “SPEC” of “DATA MONI-
TOR” mode with CONSULT-III during normal operation of the Engine Control System. When the value in
“SPEC” of “DATA MONITOR” mode is within the SP value, the Engine Control System is confirmed OK. When
the value in “SPEC” of “DATA MONITOR” mode is NO T within the SP value, the Engine Control System may
have one or more malfunctions.
The SP value is used to detect malfunctions that may af fect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:
 B/FUEL SCHDL (The fuel injection pulse width progr ammed into ECM prior to any learned on board correc-
tion)
 A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
 MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionINFOID:0000000003771321
 Vehicle driven distance: More than 5,000 km (3,107 miles)
 Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm
2 , 14.25 - 15.12 psi)
 Atmospheric temperature: 20 - 30 °C (68 - 86 °F)
 Engine coolant temperature: 75 - 95 °C (167 - 203 °F)
 Engine speed: Idle
 Transmission: Warmed-up
- After the engine is warmed up to normal operating temper ature, drive vehicle until “ATF TEMP SE 1” (A/T
fluid temperature sensor signal) indicates more than 60 °C (140 °F).
 Electrical load: Not applied
- Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureINFOID:0000000003771322
NOTE:
Perform “SPEC” in “DATA MONITOR” mode in maximum scale display.
1. Perform EC-13, "Basic Inspection"
.
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2” and “MAS A/F SE-B1” in “SPEC” of “DATA
MONITOR” mode with CONSULT-III.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-75, "Diagnosis Procedure"
.
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EC-78
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
>> GO TO 8.
8.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> GO TO 9.
9.PERFORM POWER BALANCE TEST
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Make sure that the each cylinder produces a momentary engine speed drop.
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10.DETECT MALFUNCTIONING PART
1. Check the following.
- Ignition coil and its circuit (Refer to EC-404, "Diagnosis Procedure"
.)
- Fuel injector and its circuit (Refer to EC-392, "Diagnosis Procedure"
.)
- Intake air leakage
- Low compression pressure (Refer to EM-23, "Checking Compression Pressure"
.)
2. If NG, repair or replace the malfunctioning part.
If OK, replace fuel injector. (It may be caus ed by leakage from fuel injector or clogging.)
>> GO TO 11.
11 .CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> GO TO 12.
12.CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.
 For DTC P0130, P0150, refer to EC-136, "DTC Confirmation Procedure"
.
 For DTC P0131, P0151, refer to EC-140, "DTC Confirmation Procedure"
.
 For DTC P0132, P0132, refer to EC-143, "DTC Confirmation Procedure"
.
 For DTC P0133, P0153, refer to EC-146, "DTC Confirmation Procedure"
.
 For DTC P2A00, P2A03, refer to EC-377, "DTC Confirmation Procedure"
.
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13.CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
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TROUBLE DIAGNOSIS - SPECIFICATION VALUEEC-79
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OK >>
INSPECTION END
NG >> GO TO 15.
15.DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin term inal and connector for damage, and then reconnect it.
>> GO TO 16.
16.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> Detect malfunctioning part according to EC-475, "Symptom Matrix Chart"
.
17.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” m ode, and make sure that the indication is within the
SP value.
OK or NG
OK >> INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18.DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
- Engine oil level is too high
- Engine oil viscosity
- Belt tension of power steering, alternator, A/C compressor, etc. is excessive
- Noise from engine
- Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
- Valve clearance malfunction
- Intake valve timing control function malfunction
- Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 30.
19.CHECK INTAKE SYSTEM
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
OK or NG
OK >> GO TO 21.
NG >> Repair or replace malfunctioning part, and then GO TO 20.
20.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/F UEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG (“B/FUEL SCHDL” is more, “A/F ALPHA-B1”, “A /F ALPHA-B2” are less than the SP value)>>GO TO 21.
21.DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR
1. Stop the engine.
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EC-80
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
2. Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and
then reconnect it again.
>> GO TO 22.
22.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> 1. Detect malfunctioning part of mass air flow sensor circuit and repair it. Refer to EC-109 .
2. GO TO 29.
NG >> GO TO 23.
23.CHECK “MAS A/F SE-B1”
Select “MAS A/F SE-B1” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the
SP value.
OK or NG
OK >> GO TO 24.
NG (More than the SP value)>>Replace mass air flow sensor, and then GO TO 29.
24.REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS(NAT S) system and registration of all IVIS(NATS) ignition key IDs. Refer to
SEC-6, "ECM RE-COMMUNICATING FUNCT ION : Special Repair Requirement"
.
3. Perform EC-17, "VIN Registration"
.
4. Perform EC-18, "Accelerator Pedal Released Position Learning"
.
5. Perform EC-18, "Throttle Valve Closed Position Learning"
.
6. Perform EC-18, "Idle Air Volume Learning"
.
>> GO TO 29.
25.CHECK INTAKE SYSTEM
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
OK or NG
OK >> GO TO 27.
NG >> Repair or replace malfunctioning part, and then GO TO 26.
26.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the
SP value.
OK or NG
OK >> INSPECTION END
NG (Less than the SP value)>>GO TO 27.
27.CHECK “MAS A/F SE-B1”
Select “MAS A/F SE-B1” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the
SP value.
OK or NG
OK >> GO TO 28.
NG (Less than the SP value)>>Replace mass air flow sensor, and then GO TO 30.
28.CHECK INTAKE SYSTEM
Check for the cause of air leak after the mass air flow sensor. Refer to the following.
Revision: December 20092009 QX56

P0011, P0021 IVT CONTROLEC-87
< COMPONENT DIAGNOSIS > [VK56DE]
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P0011, P0021 IVT CONTROL
On Board Diagnosis LogicINFOID:0000000003771334
FAIL-SAFE MODE
When the malfunction is detected,
the ECM enters fail-safe mode.
DTC Confirmation ProcedureINFOID:0000000003771335
CAUTION:
Always drive at a safe speed.
NOTE:
If DTC P0011 or P0021 is displayed with DTC P0075, P0081, P1140 or P1145, first perform the trouble
diagnosis for EC-100
or EC-291.
 If DTC Confirmation Procedure has been previously c onducted, always perform the following before con-
ducting the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is between 10V and 16V at
idle.
PROCEDURE FOR MALFUNCTION A
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-III.
3. Maintain the following conditions for at least 10 consecutive seconds.
DTC No. Trouble diagnosis name Detecting condition Possible cause
P0011
0011
(Bank 1)
Intake valve timing control
performance A
The alignment of the intake valve timing
control has been misresistered.  Harness or connectors
(Intake valve timing control solenoid
valve circuit is open or shorted.)
 Harness or connectors (Intake valve timing control position
sensor circuit is open or shorted.)
 Intake valve timing control solenoid valve
 Intake valve timing control position sensor
 Crankshaft position sensor (POS)
 Camshaft position sensor (PHASE)
 Accumulation of debris to the signal
pick-up portion of the camshaft
sprocket
 Timing chain installation
 Foreign matter caught in the oil groove for intake valve timing control
P0021
0021
(Bank 2)
B
There is a gap between angle of target and
phase-control angle degree.
Detected items Engine operating condition in fail-safe mode
Intake valve timing control The signal is not energized to the solenoid valve and the valve control does not function
ENG SPEED More than 2,000 rpm (A constant rotation is maintained.)
COOLAN TEMP/S More than 70 °C (158 °F)
Selector lever 1st or 2nd position
Driving location uphill Driving vehicle uphill
(Increased engine load will help maintain the driving con-
ditions required for this test.)
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P0011, P0021 IVT CONTROLEC-89
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OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK INTAKE VALVE TIMING CONTROL PO
SITION SENSOR POWER SUPPLY CIRCUIT
1. Disconnect intake valve timing control position sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between intake valve timing control position sen- sor terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32
 Harness for open or short between intake valve timing control position sensor and ECM
 Harness for open or short between intake valve timing control position sensor and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK INTAKE VALVE TIMING CONTROL POSI TION SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between intake valve ti ming control position sensor terminal 1 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32
 Harness for open or short between intake valve timing control position sensor and ground
1. Intake valve timing control position sensor (bank 2) 2. Intake valve timing control solenoid
valve (bank 2) 3. Drive belt
4. Radiator hose 5. Intake valve timing control solenoid valve (bank 1)6. Intake valve timing control position
sensor (bank 1)
Voltage: Battery voltage
BBIA0771E
PBIB2613E
Continuity should exist.
Revision: December 20092009 QX56

EC-90
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P0011, P0021 IVT CONTROL
>> Repair open circuit or short to power in harness or connectors.
7.CHECK INTAKE VALVE TIMING CONTROL POSITI
ON SENSOR INPUT SIGNAL CIRCUIT FOR OPEN
AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between the following;
ECM terminal 72 and intake valve timing control position sensor (Bank 1) terminal 2 or
ECM terminal 53 and intake valve timing control position sensor (Bank 2) terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR
Refer to EC-92, "Component Inspection"
.
OK or NG
OK >> GO TO 9.
NG >> Replace malfunctioning intake valve timing control position sensor. Refer to EC-493
.
9.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Reconnect ECM harness connector.
2. Disconnect intake valve timing control solenoid valve harness connector.
3. Turn ignition switch ON.
4. Check voltage between intake valve timing control solenoid valve terminal 2 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32 Continuity should exist.
1. Intake valve timing control position
sensor (bank 2) 2. Intake valve timing control solenoid
valve (bank 2) 3. Drive belt
4. Radiator hose 5. Intake valve timing control solenoid valve (bank 1)6. Intake valve timing control position
sensor (bank 1)
Voltage: Battery voltage
BBIA0771E
PBIB0351E
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P0011, P0021 IVT CONTROLEC-91
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 Harness for open or short between intake valve timing control solenoid valve and IPDM E/R.
>> Repair open circuit or short to ground or short to power in harness or connectors.
11 .CHECK INTAKE VALVE TIMING CONTROL SOLENO ID VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN
AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between the following; ECM terminal 10 and intake valve timing control solenoid valve (Bank 1) terminal 1 or
ECM terminal 11 and intake valve timing control solenoid valve (Bank 2) terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE
Refer to EC-92, "Component Inspection"
.
OK or NG
OK >> GO TO 13.
NG >> Replace malfunctioning intake valve timing control solenoid valve. Refer to EC-492
.
13.CHECK CRANKSHAFT POSITION SENSOR (POS)
Refer to EC-200, "Component Inspection"
.
OK or NG
OK >> GO TO 14.
NG >> Replace crankshaft position sensor (POS).
14.CHECK CAMSHAFT POSIT ION SENSOR (PHASE)
Refer to EC-204, "Component Inspection"
.
OK or NG
OK >> GO TO 15.
NG >> Replace malfunctioning camshaft position sensor (PHASE). Refer to EC-493
.
15.CHECK CAMSHAFT SPROCKET
Check accumulation of debris to the signal pick- up portion of the camshaft sprocket. Refer to EM-62, "Inspec-
tion after Installation".
OK or NG
OK >> GO TO 16.
NG >> Remove debris and clean the signal pick-up cutout of camshaft sprocket.
16.CHECK TIMING CHAIN INSTALLATION
Check service records for any recent repairs that may cause timing chain misaligned.
Are there any service records that may cause timing chain misaligned?
Ye s o r N o
Yes >> Check timing chain installation. Refer to EM-45, "Removal and Installation".
No >> GO TO 17.
17.CHECK LUBRICATION CIRCUIT
Refer to EM-62, "Inspection after Installation"
.
OK or NG
OK >> GO TO 18.
NG >> Clean lubrication line. Continuity should exist.
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EC-92
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P0011, P0021 IVT CONTROL
18.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771337
INTAKE VALVE TIMING CONTROL POSITION SENSOR
1. Disconnect intake valve timing control position sensor harness connector.
2. Loosen the fixing bolt of the sensor.
3. Remove the sensor.
4. Visually check the sensor for chipping.
5. Check resistance as shown below.
6. If NG, replace intake valve timing control position sensor. Refer
to EC-493
.
INTAKE VALVE TIMING CONTROL SOLENOID VALVE
1. Disconnect intake valve timing control solenoid valve harness connector.
2. Check resistance between intake valve timing control solenoid
valve terminals as follows.
If NG, replace intake valve timing control solenoid valve. Refer to
EC-492
.
If OK, go to next step.
3. Remove intake valve timing control solenoid valve. Refer to EC-
492.
SEF362Z
Terminal No. (Polarity) Resistance Ω [at 25 °C (77 °F)]
3 (+) - 1 (-) Except 0 or ∞
2 (+) - 1 (-)
3 (+) - 2 (-)
JMBIA0600ZZ
Terminals Resistance
1 and 2 7.1 - 7.7 Ω [at 20 °C (68 °F)]
1 or 2 and ground ∞Ω
(Continuity should not exist)
MBIB0027E
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EC-94
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P0031, P0032, P0051, P00
52 A/F SENSOR 1 HEATER
P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
DescriptionINFOID:0000000003771338
SYSTEM DESCRIPTION
The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F sensor 1 element at the specified range.
On Board Diagnosis LogicINFOID:0000000003771339
DTC Confirmation ProcedureINFOID:0000000003771340
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following pr ocedure, confirm that battery voltage is between 10.5V and 16V at
idle.
1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-94, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771341
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Air fuel ratio (A/F) sensor 1
heater control Air fuel ratio (A/F) sensor 1
heater
Mass air flow sensor Amount of intake air
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0031
0031
(Bank 1) Air fuel ratio (A/F) sensor
1 heater control circuit low The current amperage in the air fuel ratio (A/F) sen-
sor 1 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the air fuel ratio (A/F) sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
 A/F sensor 1 heater
P0051
0051
(Bank 2)
P0032
0032
(Bank 1)
Air fuel ratio (A/F) sensor
1 heater control circuit
high The current amperage in the air fuel ratio (A/F) sen-
sor 1 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the air fuel ratio (A/F) sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
 A/F sensor 1 heater
P0052
0052
(Bank 2)
Revision: December 20092009 QX56