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P2138 APP SENSOREC-375
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4.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
INFINITI QX56 2009 Factory Service Manual
P2138 APP SENSOREC-375
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4.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.](/manual-img/42/57031/w960_57031-1701.png)
P2138 APP SENSOREC-375
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4.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between APP sensor terminal 6 and ECM terminal 91. Refer to Wiring Diagram.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit in harness or connectors.
5.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals
OK or NG
OK >> GO TO 6.
NG >> Repair short to ground or short to power in harness connectors.
6.CHECK THROTTLE POSITION SENSOR
Refer to EC-372, "Component Inspection"
.
OK or NG
OK >> GO TO 12.
NG >> GO TO 7.
7.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-18, "Throttle Valve Closed Position Learning"
.
3. Perform EC-18, "Idle Air Volume Learning"
.
>> INSPECTION END
8.CHECK APP SENSOR GROUND CI RCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 82 and APP sensor terminal 1, ECM terminal 83 and
APP sensor terminal 3.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 106 and APP sensor terminal 2, ECM terminal 98 and APP sensor terminal 5.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power. Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 2 EC-432, "Wiring Diagram - ENGINE
CONTROL SYSTEM -"91 APP sensor terminal 6
Continuity should exist.
Continuity should exist.
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual
EC-380
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
2. Disconnect A/F sensor 1 harness connector.
3. Check harness connector for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace h INFINITI QX56 2009 Factory Service Manual
EC-380
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
2. Disconnect A/F sensor 1 harness connector.
3. Check harness connector for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace h](/manual-img/42/57031/w960_57031-1706.png)
EC-380
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
2. Disconnect A/F sensor 1 harness connector.
3. Check harness connector for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness connector.
6.CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check voltage between A/F sensor 1 terminal 4 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.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.
8.CHECK A/F SENSOR 1 INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.Water should not exit.
BBIA0376E
Voltage: Battery voltage
PBIB3308E
A/F sensor 1 terminal ECM terminal
Bank1 135
256
Bank 2 116
275
Continuity should exist.
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual
EC-384
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
OK or NG
OK >>
INSPECTION END
NG >> GO TO 7.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD br INFINITI QX56 2009 Factory Service Manual
EC-384
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
OK or NG
OK >>
INSPECTION END
NG >> GO TO 7.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD br](/manual-img/42/57031/w960_57031-1710.png)
EC-384
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
OK or NG
OK >>
INSPECTION END
NG >> GO TO 7.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness connectors M31, E152
Fuse block (J/B) connector M4
10A fuse
Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2. Refer to Wiring Diagram.
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
BBIA0373E
Voltage: Battery voltage
PBIB0857E
Continuity should exist.
Revision: December 20092009 QX56
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ASCD BRAKE SWITCHEC-385
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4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circui INFINITI QX56 2009 Factory Service Manual
ASCD BRAKE SWITCHEC-385
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4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circui](/manual-img/42/57031/w960_57031-1711.png)
ASCD BRAKE SWITCHEC-385
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4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ASCD BRAKE SWITCH
Refer to EC-386, "Component Inspection"
.
OK or NG
OK >> GO TO 11.
NG >> Replace ASCD brake switch.
7.CHECK STOP LAMP SWIT CH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT -IIl or tester.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
Harness connectors M31, E152
Fuse block (J/B) connector M60
10A fuse
Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK STOP LAMP SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 10.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0373E
Voltage: Battery voltage
PBIB2102E
Continuity should exist.
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual
EC-388
< COMPONENT DIAGNOSIS >[VK56DE]
COOLING FAN
COOLING FAN
Diagnosis ProcedureINFOID:0000000003771708
1.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness conn INFINITI QX56 2009 Factory Service Manual
EC-388
< COMPONENT DIAGNOSIS >[VK56DE]
COOLING FAN
COOLING FAN
Diagnosis ProcedureINFOID:0000000003771708
1.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness conn](/manual-img/42/57031/w960_57031-1714.png)
EC-388
< COMPONENT DIAGNOSIS >[VK56DE]
COOLING FAN
COOLING FAN
Diagnosis ProcedureINFOID:0000000003771708
1.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E120.
3. Check voltage between IPDM E/R terminal 22 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
40A fusible link
Harness for open or short between IPDM E/R and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
3.CHECK COOLING FAN MOTOR CIRCUIT FOR OPEN OR SHORT
1. Disconnect cooling fan motor harness connector (1).
2. Check harness continuity between cooling fan motor terminal 2 and IPDM E/R terminal 24, cooling fan motor terminal 1 and
ground.
Refer to wiring diagram.
3. 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 COOLING FAN MOTOR
Refer to EC-388, "Component Inspection"
.
OK or NG
OK >> GO TO 5.
NG >> Replace cooling fan motor.
5.CHECK INTERMITTENT INCIDENT
Perform GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
OK or NG
OK >> Replace IPDM E/R. Refer to PCS-34, "Removal and Installation of IPDM E/R".
NG >> Repair or replace harness connectors.
Component InspectionINFOID:0000000003771709
COOLING FAN MOTOR
1. Disconnect cooling fan motor harness connector. Voltage: Battery voltage
PBIB2067E
Continuity should exist.
BBIA0742E
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FUEL INJECTOREC-393
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2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector INFINITI QX56 2009 Factory Service Manual
FUEL INJECTOREC-393
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2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector](/manual-img/42/57031/w960_57031-1719.png)
FUEL INJECTOREC-393
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2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector terminal 1 and ground with
CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E2, F32
IPDM E/R connector E119
15A fuse
Harness for open or short between fuel injector and fuse
>> Repair harness or connectors.
5.CHECK FUEL INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between fuel injector te rminal 2 and ECM terminals 21, 22, 23, 40, 41, 42, 44,
63.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK FUEL INJECTOR
Refer to EC-394, "Component Inspection"
.
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning fuel injector.
7.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Voltage: Battery voltage
BBIA0374E
PBIB0582E
Continuity should exist.
Revision: December 20092009 QX56
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FUEL PUMPEC-397
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2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7.CHECK CONDENSER-2 POWER SUPPL INFINITI QX56 2009 Factory Service Manual
FUEL PUMPEC-397
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2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7.CHECK CONDENSER-2 POWER SUPPL](/manual-img/42/57031/w960_57031-1723.png)
FUEL PUMPEC-397
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2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7.CHECK CONDENSER-2 POWER SUPPLY
CIRCUIT-II FOR OPEN AND SHORT
1. Disconnect IPDM E/R harness connector E119.
2. Check harness continuity between IPDM E/R terminal 13 and condenser-2 terminal 1. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK CONDENSER-2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between condenser-2
+ terminal 2 and ground.
Refer to Wiring Diagram.
2. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9.CHECK CONDENSER-2
Refer to EC-398, "Component Inspection"
.
OK or NG
OK >> GO TO 10.
NG >> Replace condenser-2.
10.CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “fuel level sensor unit and fuel pump” harness con- nector.
3. Disconnect IPDM E/R harness connector E119.
4. Check harness continuity between IPDM E/R terminal 13 and “fuel level sensor unit and fuel pump” terminal 1, “fuel level sen-
sor unit and fuel pump” terminal 3 and ground.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E41, C1
Harness for open or short between fuel pump and IPDM E/R
Harness for open or short between fuel pump and ground Continuity should exist.
Continuity should exist.
Continuity should exist.
BBIA0583E
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ICC BRAKE SWITCHEC-401
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1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check harness continuity betw INFINITI QX56 2009 Factory Service Manual
ICC BRAKE SWITCHEC-401
< COMPONENT DIAGNOSIS > [VK56DE]
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1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check harness continuity betw](/manual-img/42/57031/w960_57031-1727.png)
ICC BRAKE SWITCHEC-401
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1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check harness continuity between ICC brake hold relay terminal
3 and ICC brake switch terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK ICC BRAKE SWITCH INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108. Refer 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 ICC BRAKE HOLD RELAY
Refer to EC-402, "Component Inspection"
.
OK >> GO TO 9.
NG >> Replace ICC brake hold relay.
9.CHECK ICC BRAKE SWITCH
Refer to EC-402, "Component Inspection"
.
OK or NG
OK >> GO TO 14.
NG >> Replace ICC brake switch.
10.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector. Continuity should exist.
BBIA0470E
Continuity should exist.
BBIA0470E
Revision: December 20092009 QX56