ignition INFINITI QX56 2008 Factory Service Manual

EC-92
< COMPONENT DIAGNOSIS >[VK56DE]
P0011, P0021 IVT CONTROL
Refer to EC-86, "Ground Inspection".
OK or NG
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 timing control position sensor terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0354E
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
SEF509Y
Revision: March 2010 2008 QX56

P0011, P0021 IVT CONTROLEC-93
< COMPONENT DIAGNOSIS > [VK56DE]
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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
>> Repair open circuit or short to power in harness or connectors.
7.CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN
AND SHORT1. 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 contro l 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-95, "
Component Inspection".
OK or NG
OK >> GO TO 9.
NG >> Replace malfunctioning intake valve timing control position sensor. Refer to EC-501
.
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. Continuity should exist.
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)
BBIA0771E
Revision: March 2010 2008 QX56

EC-94
< COMPONENT DIAGNOSIS >[VK56DE]
P0011, P0021 IVT CONTROL
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
• Harness for open or short between intake valv e 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 SOLENOID 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-95, "
Component Inspection".
OK or NG
OK >> GO TO 13.
NG >> Replace malfunctioning intake valve timing control solenoid valve. Refer to EC-500
.
13.CHECK CRANKSHAFT POSI TION SENSOR (POS)
Refer to EC-209, "
Component Inspection".
OK or NG
OK >> GO TO 14.
NG >> Replace crankshaft position sensor (POS).
14.CHECK CAMSHAFT POSITI ON SENSOR (PHASE)
Refer to EC-213, "
Component Inspection".
OK or NG
OK >> GO TO 15.
NG >> Replace malfunctioning camshaft position sensor (PHASE). Refer to EC-501
.
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. Voltage: Battery voltage
PBIB0351E
Continuity should exist.
Revision: March 2010
2008 QX56

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
EC-97
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P0031, P0032, P0051, P0052
A/F SENSOR 1 HEATER
DescriptionINFOID:0000000001351384
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:0000000001351378
DTC Confirmation ProcedureINFOID:0000000001351379
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is between 10.5V and 16V at
idle.
WITH CONSULT-III
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-97, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351381
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 functionActuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Air fuel ratio (A/F) sensor 1
heater controlAir fuel ratio (A/F) sensor 1
heater
Mass air flow sensor Amount of intake air
DTC No. Trouble diagnosis name DTC detecting conditionPossible 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: March 2010
2008 QX56

EC-98
< COMPONENT DIAGNOSIS >[VK56DE]
P0031, P0032, P0051, P00
52 A/F SENSOR 1 HEATER
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check voltage between A/F sensor 1 terminal 4 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• IPDM E/R harness connector E119
• 15A fuse
• Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.
4.CHECK A/F SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 2 (bank 1) or 24, 43 (bank 2) and A/F sensor 1 terminal
3.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
BBIA0354E
Voltage: Battery voltage
BBIA0376E
PBIB3308E
Continuity should exist.
Revision: March 2010 2008 QX56

EC-100
< COMPONENT DIAGNOSIS >[VK56DE]
P0037, P0038, P0057,
P0058 HO2S2 HEATER
P0037, P0038, P0057, P0058 HO2S2 HEATER
DescriptionINFOID:0000000001351385
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxy gen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
On Board Diagn osis LogicINFOID:0000000001351387
DTC Confirmation ProcedureINFOID:0000000001351388
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following pr ocedure, confirm that battery voltage is between 10.5V and 16V at
idle.
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start the engine and keep the engine speed between 3,500 rpm and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Check 1st trip DTC.
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Heated oxygen sensor 2
heater controlHeated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600 OFF
Below 3,600 rpm after the following conditions are met.
• Engine: After warming up
• Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load ON
DTC No. Trouble diagnosis name
DTC detecting conditionPossible cause
P0037
0037
(Bank 1) Heated oxygen sensor 2
heater control circuit low The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(The heated oxygen sensor 2 heater
circuit is open or shorted.)
• Heated oxygen sensor 2 heater
P0057
0057
(Bank 2)
P0038
0038
(Bank 1)
Heated oxygen sensor 2
heater control circuit high The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(The heated oxygen sensor 2 heater
circuit is shorted.)
• Heated oxygen sensor 2 heater
P0058
0058
(Bank 2)
Revision: March 2010
2008 QX56

P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-101
< COMPONENT DIAGNOSIS > [VK56DE]
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7. If 1st trip DTC is detected, go to
EC-101, "Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351390
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-86, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Turn ignition switch ON.
3. Check voltage between HO2S2 terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• IPDM E/R harness connector E119
• 15A fuse
• Harness for open or short between heated oxygen sensor 2 and fuse
>> Repair harness or connectors.
BBIA0354E
BBIA0435E
Voltage: Battery voltage
PBIB0112E
Revision: March 2010 2008 QX56

EC-102
< COMPONENT DIAGNOSIS >[VK56DE]
P0037, P0038, P0057,
P0058 HO2S2 HEATER
4.CHECK HO2S2 HEATER OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal and HO2S2 terminal as follows. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-102, "
Component Inspection".
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 2.
6.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001351391
HEATED OXYGEN SENSOR 2 HEATER
1. Check resistance between HO2S2 terminals as follows.
2. If NG, replace heated oxygen sensor 2.
CAUTION:
• Discard any heated oxygen 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 oxygen sensor, clean exhaust system
threads using Oxygen Sensor Thread Cleaner tool J-43897-18
or J-43897-12 and approved anti-seize lubricant.
DTC Te r m i n a l s
Bank
ECM Sensor
P0037, P0038 6 21
P0057, P0058 25 22
Continuity should exist.
Terminal No. Resistance
2 and 3 8 - 10 Ω at 25°C (77 °F)
1 and 2, 3, 4 ∞ Ω
(Continuity should not exist)
4 and 1, 2, 3
SEF249Y
Revision: March 2010 2008 QX56

P0075, P0081 IVT CONTROL SOLENOID VALVEEC-103
< COMPONENT DIAGNOSIS > [VK56DE]
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P0075, P0081 IVT CONTROL SOLENOID VALVE
Component DescriptionINFOID:0000000001351393
Intake valve timing control solenoid valve is activated by ON/OFF
pulse duty (ratio) signals from the ECM.
The intake valve timing control solenoid valve changes the oil
amount and direction of flow through intake valve timing control unit
or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
On Board Diagnosis LogicINFOID:0000000001351395
DTC Confirmation ProcedureINFOID:0000000001351396
NOTE:
If DTC Confirmation Procedure has been previously conducted, alw
ays turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Start engine and let it idle for 5 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-103, "
Diagnosis Procedure".
WITH GST
Following the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351398
1.CHECK INTAKE VALVE TIMING CONTROL SO LENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect intake valve timing control solenoid valve harness connector.
PBIB1842E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0075
0075
(Bank 1) Intake valve timing control
solenoid valve 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
0081
(Bank 2)
BBIA0771E
Revision: March 2010
2008 QX56

EC-104
< COMPONENT DIAGNOSIS >[VK56DE]
P0075, P0081 IVT CONTROL SOLENOID VALVE
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 3.
NG >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E2, F32
• IPDM E/R harness connector E119
• 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.
3.CHECK INTAKE VALVE TIMING CONTROL SOLENOID 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 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK INTAKE VALVE TIMING CONTROL SOLENOID VALVE
Refer to EC-104, "
Component Inspection".
OK or NG
OK >> GO TO 5.
NG >> Replace malfunctioning intake valve timing control solenoid valve. Refer to EC-500
.
5.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001351399
INTAKE VALVE TIMING CONTROL SOLENOID VALVE
1. Disconnect intake valve timing control solenoid valve harness connector.
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
PBIB0351E
Continuity should exist.
Revision: March 2010 2008 QX56