2011 INFINITI QX56 BATTERY CONNECTORS

EC-326
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0447 EVAP CANISTER VENT CONTROL VALVE
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between EVAP canister vent control valve and IPDM E/R
 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 EVAP CANISTER VENT CONTROL VALVE OU TPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP canister v ent control valve harness connector and ECM harness con-
nector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Loose or poor connection for each connector and harness
 Harness for open or short between EVAP canister vent control valve and ECM
>> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK RUBBER TUBE FOR CLOGGING
1. Disconnect rubber tube connected to EV AP canister vent control valve.
2. Check the rubber tube for clogging.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Clean the rubber tube using an air blower.
8.CHECK EVAP CANISTER VENT CONTROL VALVE
Refer to EC-327, "
Component Inspection (EVAP Canister Vent Control Valve)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Replace EVAP canister vent control valve. Refer to FL-10, "
Exploded View".
9.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
EVAP canister vent control valve Ground Voltage
Connector Terminal
C18 1 Ground Battery voltage
EVAP canister vent control valve ECM
Continuity
Connector Terminal Connector Terminal
C18 2 E80 120 Existed
Revision: 2010 May2011 QX56

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOREC-333
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0451 EVAP CONTROL SYSTEM
PRESSURE SENSOR
DTC LogicINFOID:0000000006288316
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and wait at least 40 seconds. NOTE:
Do not depress accelerator pedal even slightly.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-333, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288317
1.CHECK EVAP CONTRO L SYSTEM PRESSURE SENSOR CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check that water is not inside connectors.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace harness connector.
2.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check the voltage between EVAP control system pressure sensor harness connector and ground.
DTC No. Trouble diagnosis name
(Trouble diagnosis con- tent) DTC detecting condition Possible cause
P0451 EVAP SYS PRES SEN
(EVAP control system
pressure sensor perfor-
mance) ECM detects a sloshing signal
from the EVAP control system
pressure sensor  (EVAP control system pressure sensor circuit is shorted.)
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
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
EVAP control system
pressure sensor Ground Voltage (V)
Connector Terminal
C17 3 Ground Approx. 5 V
Revision: 2010 May2011 QX56

EC-334
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0451 EVAP CONTROL S
YSTEM PRESSURE SENSOR
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 3.
3.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 4.
NO >> Repair short to ground or short to power in harness or connectors.
4.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)".)
 Battery current sensor (Refer to EC-427, "
Component Inspection (Battery Current Sensor)".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace malfunctioning component.
5.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 6.
6.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly.
Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASS IST SYSTEM : Removal and Installation"
(Without distance control assist system)
Refer to ACC-4, "
MODELS WITH DISTANCE CONTROL ASSI ST SYSTEM : Removal and Installation" (With
distance control assist system).
>> INSPECTION END
7.CHECK EVAP CONTROL SY STEM PRESSURE SENSOR
Refer to EC-335, "
Component Inspection (EVAP Control System Pressure Sensor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace EVAP control system pressure sensor.
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 Crankshaft position sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 133EVAP control system pressure sen-
sor
C17 3
Battery current sensor E63 2
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-336
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0452 EVAP CONTROL S
YSTEM PRESSURE SENSOR
P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR
DTC LogicINFOID:0000000006288319
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:
Always perform test at a temperature of 5 °C (41 °F) or more.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
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. Turn ignition switch ON.
6. Select “DATA MONITOR” mode with CONSULT-III.
7. Check that “FUEL T/TM P SE” is more than 0°C (32 °F).
8. Start engine and wait at least 20 seconds.
9. Check 1st trip DTC.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes to ECM harness connector terminals under the following conditions.
3. Check that the voltage is less than 4.2 V.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON.
6. Turn ignition switch OFF and wait at least 10 seconds.
7. Start engine and wait at least 20 seconds.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0452 EVAP SYS PRES SEN
(EVAP control system pres-
sure sensor low input) An excessively low voltage from
the sensor is sent to ECM.  (EVAP control system pressure sensor circuit is short-
ed.)
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
 Battery current sensor
 Accelerator pedal position sensor
 Camshaft position sensor (bank 1)
 Crankshaft position sensor
 Refrigerant pressure sensor
ECM
Connector +–
Terminal Terminal
E80 134
(Fuel tank temperature sensor signal) 175
Revision: 2010 May2011 QX56

EC-338
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0452 EVAP CONTROL S
YSTEM PRESSURE SENSOR
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair short to ground or short to power in harness or connectors.
6.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)".)
 Battery current sensor (Refer to EC-414, "
Component Inspection (Battery Current Sensor)".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace malfunctioning component.
7.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 14.
NO >> GO TO 8.
8.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly.
Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASS IST SYSTEM : Removal and Installation"
(Without distance control assist system)
Refer to ACC-4, "
MODELS WITH DISTANCE CONTROL ASSI ST SYSTEM : Removal and Installation" (With
distance control assist system).
>> INSPECTION END
9.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP control system pressure sensor harness connector and ECM har-
ness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 11.
NO >> GO TO 10.
10.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between EVAP control system pressure sensor and ECM
E80 133EVAP control system pressure sen-
sor
C17 3
Battery current sensor E63 2
Refrigerant pressure sensor E77 1
131 APP sensor 2 (Without ICC) E110 1
APP sensor 2 (with ICC) E67 9
ECM Sensor
Connector Terminal Name Connector Terminal
EVAP control system pressure sensor ECM
Continuity
Connector Terminal Connector Terminal
C17 1 E80 150 Existed
Revision: 2010 May2011 QX56

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOREC-341
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0453 EVAP CONTROL SYSTEM
PRESSURE SENSOR
DTC LogicINFOID:0000000006288322
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:
Always perform test at a temperature of 5 °C (41 °F) or more.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
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. Turn ignition switch ON.
6. Select “DATA MONITOR” mode with CONSULT-III.
7. Check that “FUEL T/TM P SE” is more than 0°C (32 °F).
8. Start engine and wait at least 20 seconds.
9. Check 1st trip DTC.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes to ECM harness connector terminals under the following conditions.
3. Check that the voltage is less than 4.2 V.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0453 EVAP SYS PRES SEN
(EVAP control system pres-
sure sensor high input) An excessively high voltage
from the sensor is sent to
ECM.  Harness or connectors
(EVAP control system pressure sensor circuit is short-
ed.)
(Crankshaft position sensor circuit is open or shorted.)
[Camshaft position sensor (bank 1) circuit is shorted.]
(Accelerator pedal position sensor 2 circuit is shorted.)
(Battery current sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
 EVAP control system pressure sensor
 Crankshaft position sensor
 Camshaft position sensor (bank 1)
 Accelerator pedal position sensor 2
 Battery current sensor
 Refrigerant pressure sensor
 EVAP canister vent control valve
 EVAP canister
 Rubber hose from EVAP canister vent control valve to
vehicle frame
ECM Ground
Connector +–
Terminal Terminal
E80 134
(Fuel tank temperature sensor signal) 175
Revision: 2010 May2011 QX56

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOREC-343
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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EC
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Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair short to ground or short to power in harness or connectors.
6.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)".)
 Battery current sensor (Refer to EC-427, "
Component Inspection (Battery Current Sensor)".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace malfunctioning component.
7.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 8.
8.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly.
Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSI ST SYSTEM : Removal and Installation"
(Without distance control assist system)
Refer to ACC-4, "
MODELS WITH DISTANCE CONTROL ASSI ST SYSTEM : Removal and Installation" (With
distance control assist system).
>> INSPECTION END
9.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP control syst em pressure sensor harness connector and ECM har-
ness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 11.
NO >> GO TO 10.
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 Crankshaft position sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 133EVAP control system pressure sen-
sor
C17 3
Battery current sensor E63 2
Refrigerant pressure sensor E77 1
131 APP sensor 2 (Without ICC) E110 1
APP sensor 2 (with ICC) E67 9
EVAP control system
pressure sensor ECM
Continuity
Connector Terminal Connector Terminal
C17 1 E80 150 Existed
Revision: 2010 May2011 QX56

P0462, P0463 FUEL LEVEL SENSOR
EC-355
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0462, P0463 FUEL LEVEL SENSOR
DTC LogicINFOID:0000000006288333
DTC DETECTION LOGIC
NOTE:

If DTC P0462 or P0463 is displayed with DTC UXXXX, first perform the trouble diagnosis for DTC
UXXXX.
 If DTC P0462 or P0463 is displayed with DTC P0607, first perform the trouble diagnosis for DTC
P0607.Refer to EC-378, "
DTC Logic".
This diagnosis indicates the former, to detect open or short circuit malfunction.
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 ignition
switch ON.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-355, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288334
1.CHECK DTC WITH “COMBINATION METER”
Refer to MWI-30, "
CONSULT-III Function".
Is any DTC detected?
YES >> Perform trouble diagnosis of detected DTC.
NO >> GO TO 2.
2.CHECK FUEL LEVEL SENSOR SIGNAL CIRCUIT
Check fuel level sensor signal circuit. Refer to MWI-69, "
Component Function Check".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Perform trouble diagnosis of fuel level sensor signal circuit. Refer to MWI-69,
"DiagnosisProcedure".
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0462 FUEL LEVL SEN/CIRC
(Fuel level sensor circuit low
input) An excessively low voltage from the
sensor is sent to ECM.
 Harness or connectors
(The CAN communication line is open or shorted)
 Harness or connectors (The sensor circuit is open or shorted)
 Combination meter
 Fuel level sensor
P0463 FUEL LEVL SEN/CIRC
(Fuel level sensor circuit high
input) An excessively high voltage from
the sensor is sent to ECM.
Revision: 2010 May2011 QX56