2011 INFINITI QX56 Camshaft position sensor

EC-382
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0643 SENSOR POWER SUPPLY
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair short to ground or short to power in harness or connectors.
3.CHECK COMPONENTS
Check the following.
 Camshaft position sensor (bank 2) (Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".)
 Manifold absolute pressure (MAP) sensor (Refer to EC-208, "
Component Inspection (MAP Sensor)".)
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace malfunctioning component.
4.CHECK THROTTLE POSITION SENSOR
Refer to EC-220, "
Component Inspection (Throttle Position Sensor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 5.
5.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
Replace electric throttle control actuator. Refer to EM-30, "
Removal and Installation".
>> INSPECTION END
6.CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSIST
SYSTEM : Removal and Installation" (Without distance control assist system) or ACC-4, "MODELS WITH
DISTANCE CONTROL ASSIST SYSTEM : Removal and Installation" (With distance control assist system).
>> INSPECTION END
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
ECM Sensor
Connector Terminal Name Connector Terminal
F 111 81 Electric throttle control actuator F66 2
83 Camshaft position sensor (bank 2) F83 1
85 Manifold absolute pressure (MAP) sensor F65 1
E80 137 APP sensor 1 (Without ICC) E110 2
137 APP sensor 1 (With ICC) E67 12
Revision: 2010 May2011 QX56

EC-412
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1550 BATTERY CURRENT SENSOR
P1550 BATTERY CURRENT SENSOR
DTC LogicINFOID:0000000006217919
DTC DETECTION 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.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is 8 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-412, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217920
1.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-I
1. Disconnect battery current sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between battery current sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 2.
2.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1550 BAT CURRENT SENSOR
(Battery current sensor cir-
cuit range/performance) The output voltage of the battery
current sensor remains within
the specified range while engine
is running.  Harness or connectors
(Battery current sensor circuit is open or shorted.)
(Accelerator pedal position sensor 2 circuit is shorted.)
[Camshaft position sensor (bank 1) circuit is shorted.]
(Crankshaft position sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is short-
ed.)
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
 EVAP control system pressure sensor
Battery current sensor Ground Voltage (V)
Connector Terminal
E63 2 Ground Approx. 5
Revision: 2010 May2011 QX56

P1550 BATTERY CURRENT SENSOREC-413
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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3. Check the continuity between battery current
sensor harness connector and ECM harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open between battery current sensor and ECM
 Loose or poor connection for each connector and harness
>> Repair open circuit.
4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
 Crankshaft position sensor (Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".)
 Camshaft position sensor (bank 1) (Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".)
 EVAP control system pressure sensor (Refer to EC-520, "
Component Function Check".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace malfunctioning component.
6.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSIST
SYSTEM : Removal and Installation" (Without distance control assist system) or ACC-4, "MODELS WITH
DISTANCE CONTROL ASSIST SYSTEM : Removal and Installation" (With distance control assist system).
>> INSPECTION END
Battery current sensor ECM Continuity
Connector Terminal Connector Terminal
E63 2 E80 133 Existed
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 Crankshaft position sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 133
EVAP control system pressure sen-
sor
C17 3
Refrigerant pressure sensor E77 1
131 APP sensor 2 (Without ICC) E110 1
APP sensor 2 (with ICC) E67 9
Revision: 2010 May2011 QX56

EC-416
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1551, P1552 BATTERY CURRENT SENSOR
P1551, P1552 BATTERY CURRENT SENSOR
DTC LogicINFOID:0000000006217922
DTC DETECTION 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.
TESTING CONDITION:
Before performing the following pr ocedure, confirm that battery voltage is 8 V or more with ignition
switch ON
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-416, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217923
1.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-I
1. Disconnect battery current sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between battery current sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 2.
2.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-II
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1551 BAT CURRENT SENSOR
(Battery current
sensor circuit
low input) An excessively low voltage from
the sensor is sent to ECM.  Harness or connectors
(Battery current sensor circuit is open or shorted.)
(Accelerator pedal position sensor 2 circuit is
shorted.)
[Camshaft position sensor (bank 1) circuit is
shorted.]
(Crankshaft position sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is
shorted.)
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
 EVAP control system pressure sensor
P1552
Battery current sensor circuit
high input
(BAT CURRENT SENSOR) An excessively high voltage from
the sensor is sent to ECM.
Battery current sensor
Ground Voltage (V)
Connector Terminal
E63 2 Ground Approx. 5
Revision: 2010 May2011 QX56

P1551, P1552 BATTERY CURRENT SENSOREC-417
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between battery current
sensor harness connector and ECM harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open between battery current sensor and ECM
 Loose or poor connection for each connector and harness
>> Repair open circuit.
4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
 Crankshaft position sensor (Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".)
 Camshaft position sensor (bank 1) (Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".)
 EVAP control system pressure sensor (Refer to EC-520, "
Component Function Check".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace malfunctioning component.
6.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSIST
SYSTEM : Removal and Installation" (Without distance control assist system) or ACC-4, "MODELS WITH
DISTANCE CONTROL ASSIST SYSTEM : Removal and Installation" (With distance control assist system).
Battery current sensor ECM
Continuity
Connector Terminal Connector Terminal
E63 2 E80 133 Existed
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 Crankshaft position sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 133
EVAP control system pressure sen-
sor
C17 3
Refrigerant pressure sensor E77 1
131 APP sensor 2 (Without ICC) E110 1
APP sensor 2 (with ICC) E67 9
Revision: 2010 May2011 QX56

EC-420
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1553 BATTERY CURRENT SENSOR
P1553 BATTERY CURRENT SENSOR
DTC LogicINFOID:0000000006217925
DTC DETECTION 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.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is 8 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-420, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217926
1.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-I
1. Disconnect battery current sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between battery current sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 2.
2.CHECK BATTERY CURRENT SENSO R POWER SUPPLY CIRCUIT-II
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1553 BAT CURRENT SENSOR
(Battery current
sensor per-
formance) The signal voltage transmitted from
the sensor to ECM is higher than the
amount of the maximum power gener-
ation.  Harness or connectors
(Battery current sensor circuit is open or shorted.)
(Accelerator pedal position sensor 2 circuit is
shorted.)
[Camshaft position sensor (bank 1) circuit is
shorted.]
(Crankshaft position sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is
shorted.)
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
 EVAP control system pressure sensor
Battery current sensor Ground Voltage (V)
Connector Terminal
E63 2 Ground Approx. 5
Revision: 2010 May2011 QX56

P1553 BATTERY CURRENT SENSOREC-421
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between battery current
sensor harness connector and ECM harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open between battery current sensor and ECM
 Loose or poor connection for each connector and harness
>> Repair open circuit.
4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
 Crankshaft position sensor (Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".)
 Camshaft position sensor (bank 1) (Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".)
 EVAP control system pressure sensor (Refer to EC-520, "
Component Function Check".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace malfunctioning component.
6.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSIST
SYSTEM : Removal and Installation" (Without distance control assist system) or ACC-4, "MODELS WITH
DISTANCE CONTROL ASSIST SYSTEM : Removal and Installation" (With distance control assist system).
Battery current sensor ECM
Continuity
Connector Terminal Connector Terminal
E63 2 E80 133 Existed
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 Crankshaft position sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 133
EVAP control system pressure sen-
sor
C17 3
Refrigerant pressure sensor E77 1
131 APP sensor 2 (Without ICC) E110 1
APP sensor 2 (with ICC) E67 9
Revision: 2010 May2011 QX56

EC-424
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1554 BATTERY CURRENT SENSOR
P1554 BATTERY CURRENT SENSOR
DTC LogicINFOID:0000000006217928
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM COMPONENT FUNCTION CHECK
Perform Component Function Check. Refer to EC-424, "
Component Function Check".
NOTE:
Use Component Function Check to check the overall functi on of the battery current sensor circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-425, "
Diagnosis Procedure".
Component Function CheckINFOID:0000000006217929
1.PRECONDITIONING
TESTING CONDITION:
 Before performing the following procedure, confirm that battery voltage is 12.8 V or more at idle.
 Before performing the following procedure, confi rm that all load switches and A/C switch are turned
OFF.
>> GO TO 2.
2.PERFORM COMPONENT FUNCTION CHECK
WITH CONSULT-III
1. Start engine and let it idle.
2. Select “BAT CUR SEN” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BAT CUR SEN” indication for 10 seconds. “BAT CUR SEN” should be above 2,300 mV at least once.
WITHOUT CONSULT-III
1. Start engine and let it idle.
2. Check the voltage between ECM harness connector terminals as per the following.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1554 BAT CURRENT SENSOR
(Battery current
sensor per-
formance) The output voltage of the bat-
tery current sensor is lower than
the specified value while the
battery voltage is high enough.  Harness or connectors
(Battery current sensor circuit is open or shorted.)
(Accelerator pedal position sensor 2 circuit is shorted.)
[Camshaft position sensor (bank 1) circuit is shorted.]
(Crankshaft position sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is short-
ed.)
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
 EVAP control system pressure sensor
Revision: 2010 May2011 QX56