2011 INFINITI QX56 BATTERY CONNECTORS

P2A00, P2A03 A/F SENSOR 1EC-487
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P2A00, P2A03 A/F SENSOR 1
DTC LogicINFOID:0000000006217987
DTC DETECTION LOGIC
To judge the malfunction, the A/F signal computed by ECM fr
om the A/F sensor 1 signal is monitored so it will
not shift to LEAN side or RICH side.
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.
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. Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
6. Let engine idle for 1 minute.
7. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
8. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-487, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217988
1.RETIGHTEN A/F SENSOR 1
Loosen and retighten the A/F sensor 1. Refer to EX-5, "
Exploded View".
>> GO TO 2.
2.CHECK A/F SENSOR 1 CONNECTOR
1. Disconnect A/F sensor 1 harness connector.
2. Check that water is not inside connectors.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace harness connector.
3.CHECK FOR INTAKE AIR LEAKAGE
1. Reconnect A/F sensor 1 harness connector.
2. Start engine and run it at idle.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P2A00 A/F SENSOR1 (B1)
(Air fuel ratio (A/F) sensor 1 (bank 1)
circuit range/performance)  The output voltage computed by ECM from
the A/F sensor 1 signal shifts to the lean side
for a specified period.
 The A/F signal computed by ECM from the
A/F sensor 1 signal shifts to the rich side for
a specified period.  A/F sensor 1
 A/F sensor 1 heater
 Fuel pressure
 Fuel injector
 Intake air leaks
P2A03 A/F SENSOR1 (B2)
(Air fuel ratio (A/F) sensor 1 (bank 2)
circuit range/performance)
Revision: 2010 May2011 QX56

EC-490
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ASCD BRAKE SWITCH
ASCD BRAKE SWITCH
Component Function CheckINFOID:0000000006217989
1.CHECK ASCD BRAKE SWITCH FUNCTION
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
WITHOUT CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-490, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006217990
1.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 the voltage between ASCD brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 10 A fuse (No. 3)
 Harness for open or short between ASCD brake switch and fuse
 Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground in harness or connectors.
3.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ASCD brake s witch harness connector and ECM harness connector.
Monitor item Condition Indication
BRAKE SW1
(ASCD brake switch) Brake pedalSlightly depressed OFF
Fully released ON
ECM Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
E80 147
(ASCD brake switch signal) 175 Brake pedalSlightly depressed Approx. 0
Fully released Battery voltage
ASCD brake switch
Ground Voltage
Connector Terminal
E109 1 Ground Battery voltage
Revision: 2010 May2011 QX56

EC-504
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ICC BRAKE SWITCH
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 3.
3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 4.
4.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-II
Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block (J/B) connector E103
 10 A fuse (No. 3)
 Harness for open or short between ICC brake switch and fuse
>> Repair open circuit or short to ground in harness or connectors.
6.CHECK ICC BRAKE SWITCH
Refer to EC-445, "
Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Replace ICC brake switch. Refer to BR-20, "
Removal and Installation".
7.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ICC brake s witch harness connector and ECM harness connector.
ECM
Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
E80 147
(ICC brake switch signal) 175 Brake pedalSlightly depressed Approx. 0
Fully released Battery voltage
ICC brake switch
Ground Voltage
Connector Terminal
E68 2 Ground Battery voltage
ICC brake switch Ground Voltage
Connector Terminal
E68 1 Ground Battery voltage
Revision: 2010 May2011 QX56

IGNITION SIGNALEC-507
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to
EC-168, "
Diagnosis Procedure".
2.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Turn ignition switch ON.
4. Check the voltage between condenser harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 3.
3.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E7.
3. Check the continuity between IPDM E/R harness connector and condenser harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> Go to EC-168, "Diagnosis Procedure".
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between IPDM E/R and condenser
 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 CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between condenser harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
ECM
Vo l ta g e
Connector +–
Terminal Terminal
E80 171
175 Battery voltage
172
Condenser Ground Voltage
Connector Terminal
F8 1 Ground Battery voltage
IPDM E/R Condenser Continuity
Connector Terminal Connector Terminal
E15 61 F8 1 Existed
Condenser Ground Continuity
Connector Terminal
F8 2 Ground Existed
Revision: 2010 May2011 QX56

EC-508
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
YES >> GO TO 6.
NO >> Repair open circuit or short to power in harness or connectors.
6.CHECK CONDENSER
Refer to EC-510, "
Component Inspection (Condenser)"
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace condenser.
7.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Reconnect all harness connectors disconnected.
2. Disconnect ignition coil harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ignition coil harness connector and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
 Harness connector F22 and E46
 Harness for open or short between ignition coil and harness connector F22
>> Repair or replace harness or connectors.
9.CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between ignition coil harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
Ignition coil Ground Voltage
Cylinder Connector Terminal
1F75 3
Ground Battery voltage
2F76 3
3F77 3
4F78 3
5F79 3
6F80 3
7F81 3
8F82 3
Ignition coil
Ground Continuity
Cylinder Connector Terminal
1F75 2
Ground Existed
2F76 2
3F77 2
4F78 2
5F79 2
6F80 2
7F81 2
8F82 2
Revision: 2010 May2011 QX56

EC-512
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
LOW PRESSURE FUEL PUMP
LOW PRESSURE FUEL PUMP
Component Function CheckINFOID:0000000006218017
1.CHECK FUEL PUMP FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers. NOTE:
Fuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ON.
Is the inspection result normal?
YES >> INSPECTION END
NO >> EC-512, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218018
1.CHECK FPCM POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect FPCM harness connector.
3. Turn ignition switch ON.
4. Check the voltage between FPCM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform the trouble diagnosis for power supply circuit. Refer to EC-168, "
Diagnosis Procedure".
2.CHECK FPCM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check the continuity between FPCM harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit or short to power in harness or connectors.
3.CHECK FPCM INPUT AND OUTPUT CIRCUIT
1. Disconnect ECM harness connector.
2. Check the continuity between FPCM harness connector and ECM harness connector.
3. Also check harness for short to ground and to power.
Is the inspection result normal?
+ −Voltag e
FPCM
Connector Terminal B41 10 Ground Battery voltage
+ −Continuity
FPCM
Connector Terminal B41 5 Ground Existed
+ −
Continuity
FPCM ECM
Connector Terminal Connector Terminal
B41 8
E80 125
Existed
9142
Revision: 2010 May2011 QX56

EC-522
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
SNOW MODE SWITCH
SNOW MODE SWITCH
DescriptionINFOID:0000000006256403
The snow mode switch signal is sent to the combinat
ion meter from the snow mode switch. The combination
meter then sends the signal to the ECM via the CAN communication line.
The snow mode is used for driving or starting the vehicle on snowy roads or slippery areas. If the snow mode
is activated, the vehicle speed will not accelerate as quickly as normal to avoid vehicle slip. In other words,
ECM controls rapid engine torque change by controlling t he electric throttle control actuator operating speed.
Component Function CheckINFOID:0000000006256404
1.CHECK SNOW MODE SWITCH FUNCTION
1. Turn ignition switch ON.
2. Select “SNOW MODE SW” in “DATA MONITOR” mode with CONSULT-III.
3. Check “SNOW MODE SW” indication under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-522, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006256405
1.CHECK DTC WITH COMBINATION METER
Refer to MWI-30, "
CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to MWI-57, "
Work flow".
2.CHECK SNOW MODE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect snow mode switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between snow mode switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block harness connector M3
 10 A fuse (No. 13)
 Harness for open or short between snow mode switch and fuse.
>> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK SNOW MODE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
Monitor item Condition Indication
SNOW MODE SW Snow mode switch ON ON
OFF OFF
Snow mode switch
Ground Voltage
Connector Terminal
M54 12 Ground Battery voltage
Revision: 2010 May2011 QX56

ECM
EC-535
< REMOVAL AND INSTALLATION > [VK56VD]
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REMOVAL AND INSTALLATION
ECM
Removal and InstallationINFOID:0000000006218034
REMOVAL
1. Remove the battery and battery tray. Refer to
PG-164, "Removal and Installation".
2. Disconnect ECM harness connectors (1) as shown in the figure.
3. Remove ECM bracket bolts (A).
4. Separate ECM (2) and ECM bracket (3).
INSTALLATION
Install in the reverse order of removal.
CAUTION:
Must be perform additi onal service when replacing ECM. Refer to EC-143, "
Work Procedure".
JSBIA0307ZZ
Revision: 2010 May2011 QX56