2011 INFINITI QX56 engine

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-317
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0443 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE
DTC LogicINFOID:0000000006288307
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:
 Perform “DTC CONFIRMATION PROCEDURE” when the fuel level is between 1/4 and 3/4 full, and
vehicle is placed on flat level surface.
 Always perform test at a temperature of 5 to 60 °C (41 to 140 °F).
 Cool the vehicle so that engi ne coolant temperature becomes same level as ambient temperature.
Do you have CONSULT-III
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE A
WITH CONSULT-III
1. Turn ignition switch ON.
2. Check that the following condition are met. FUEL T/TMP SE: 0 - 35 °C (32 - 95 °F)
3. Start engine and wait at least 60 seconds.
4. Check 1st trip DTC.
IS 1st trip DTC detected?
OK >> Proceed to EC-318, "Diagnosis Procedure".
NG >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE B
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 “PURG VOL CN/V P1444” of “EVAPORA TIVE SYSTEM” in “DTC WORK SUPPORT” mode with
CONSULT-III.
7. Touch “START”.
8. Start engine and let it idle until “TESTING” on CO NSULT-III changes to “COMPLETED”. (It will take
approximately 10 seconds.)
If “TESTING” is not displayed afte r 5 minutes, retry from step 2.
9. Touch “SELF-DIAG RESULTS”.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0443 PURG VOLUME CONT/V
(EVAP canister purge vol-
ume control solenoid valve) A
The canister purge flow is detected dur-
ing the vehicle is stopped while the en-
gine is running, even when EVAP
canister purge volume control solenoid
valve is completely closed.  EVAP control system pressure sensor
 EVAP canister purge volume control
solenoid valve
(The valve is stuck open.)
 EVAP canister vent control valve
 EVAP canister
 Hoses (Hoses are connected incorrectly or
clogged.)
B
The canister purge flow is detected dur-
ing the specified driving conditions, even
when EVAP canister purge volume con-
trol solenoid valve is completely closed.
Revision: 2010 May2011 QX56

EC-318
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Proceed to
EC-318, "
Diagnosis Procedure".
4.PERFORM DTC CONFIRMATION PROCEDURE A
WITH GST
1. Turn ignition switch ON.
2. Set voltmeter probes to ECM harness connector terminals.
3. Start engine and wait at least 60 seconds.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-318, "Diagnosis Procedure".
NO >> GO TO 5.
5.PERFORM DTC CONFIRMATION PROCEDURE B
WITH GST
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. Start engine and let it idle for at least 20 seconds.
6. Check 1st trip DTC.
Is 1st trip DTC displayed?
YES >> Proceed to EC-318, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288308
1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
3. Turn ignition switch ON.
4. Check the voltage between EVAP canister purge vo lume control solenoid valve harness connector and
ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
 Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
 Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
ECM Voltage (V)
Connector +–
Terminal Terminal
E80 134
(Fuel tank temperature sensor signal) 175
(Sensor ground) 3.1 - 4.0
EVAP canister purge volume control solenoid valve
Ground Voltage
Connector Terminal
F48 1 Ground Battery voltage
Revision: 2010 May2011 QX56

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-319
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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3.CHECK EVAP CANISTER PURGE VOLUME CONTRO
L SOLENOID VALVE OUTPUT SIGNAL CIRCUIT
FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP canister pur ge volume control solenoid valve harness connector and
ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
4.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 5.
NO >> Replace EVAP control system pressure sensor.
5.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR
Refer to EC-335, "
Component Inspection (EVAP Control System Pressure Sensor)".
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 6.
YES-2 >> Without CONSULT-III: GO TO 7.
NO >> Replace EVAP control system pressure sensor.
6.CHECK EVAP CANISTER PURGE VO LUME CONTROL SOLENOID VALVE
WITH CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect harness connectors disconnected.
3. Start engine.
4. Perform “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-III. Check that engine speed var-
ies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 8.
NO >> GO TO 7.
7.CHECK EVAP CANISTER PURGE VO LUME CONTROL SOLENOID VALVE
Refer to EC-320, "
Component Inspection (EVAP Canister Purge Volume Control Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace EVAP canister purge volume control solenoid valve. Refer to FL-10, "
Exploded View".
8.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 9.
NO >> Clean the rubber tube using an air blower.
9.CHECK EVAP CANISTER VENT CONTROL VALVE
Refer to EC-327, "
Component Inspection (EVAP Canister Vent Control Valve)".
EVAP canister purge volume control solenoid valve ECM
Continuity
Connector Terminal Connector Terminal
F48 2 F110 64 Existed
Revision: 2010 May2011 QX56

EC-322
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0444, P0445 EVAP CANISTER P
URGE VOLUME CONTROL SOLENOID
VALVE
P0444, P0445 EVAP CANISTER PURG E VOLUME CONTROL SOLENOID
VA LV E
DTC LogicINFOID:0000000006217854
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, conf irm battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for at least 13 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-322, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217855
1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
3. Turn ignition switch ON.
4. Check the voltage between EVAP canister purge vo lume control solenoid valve harness connector and
ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 Loose or poor connection for each connector and harness
 Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0444 PURG VOLUME CONT/V
(EVAP canister purge volume
control solenoid valve circuit
open) An excessively low voltage signal is
sent to ECM through the valve  Harness or connectors
(The solenoid valve circuit is open or shorted.)
 EVAP canister purge volume control solenoid valve
P0445 PURG VOLUME CONT/V
(EVAP canister purge volume
control solenoid valve circuit
shorted) An excessively high voltage signal is
sent to ECM through the valve  Harness or connectors
(The solenoid valve circuit is shorted.)
 EVAP canister purge volume control solenoid valve
EVAP canister purge volume control solenoid valve Ground Voltage
Connector Terminal
F48 1 Ground Battery voltage
Revision: 2010 May2011 QX56

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VALVE
EC-323
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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 Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK EVAP CANISTER PURGE VOLUME CONTRO L SOLENOID VALVE OUTPUT SIGNAL CIRCUIT
FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between EVAP canister pur ge volume control solenoid valve harness connector and
ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES-1 >> With CONSULT-III: GO TO 4.
YES-2 >> Without CONSULT-III: GO TO 5.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
WITH CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine.
3. Perform “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-III. Check that engine speed var-
ies according to the valve opening.
Does engine speed vary according to the valve opening?
YES >> GO TO 6.
NO >> GO TO 5.
5.CHECK EVAP CANISTER PURGE VO LUME CONTROL SOLENOID VALVE
Refer to EC-320, "
Component Inspection (EVAP Canister Purge Volume Control Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace EVAP canister purge volume control solenoid valve.
6.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (EVAP Canister Purge Volume Control Solenoid Valve)
INFOID:0000000006288361
1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
WITH CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect EVAP purge hoses connected to EVAP c anister purge volume control solenoid valve.
4. Turn ignition switch ON.
5. Select “PURG VOL CONT/V” in “A CTIVE TEST” mode with CONSULT-III.
EVAP canister purge volume
control solenoid valve ECM
Continuity
Connector Terminal Connector Terminal
F48 2 F110 64 Existed
Revision: 2010 May2011 QX56

P0447 EVAP CANISTER VENT CONTROL VALVEEC-325
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0447 EVAP CANISTER VENT CONTROL VALVE
DTC LogicINFOID:0000000006288310
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, conf irm battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and wait at least 8 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-325, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288311
1.INSPECTION START
Will CONSULT-III be used?
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK EVAP CANISTER VENT CONTROL VALVE CIRCUIT
WITH CONSULT-III
1. Turn ignition switch OFF and then ON.
2. Select “VENT CONTROL/V” in “A CTIVE TEST” mode with CONSULT-III.
3. Touch “ON/OFF” on CONSULT-III screen.
4. Check for operating sound of the valve.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 3.
3.CHECK EVAP CANISTER VENT CONT ROL VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister vent control valve harness connector.
3. Turn ignition switch ON.
4. Check the voltage between EVAP canister vent control valve harness connector and ground.
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0447 VENT CONTROL VALVE
(EVAP canister vent control
valve circuit open) An improper voltage signal is sent to ECM
through EVAP canister vent control valve.  Harness or connectors
(The valve circuit is open or shorted.)
 EVAP canister vent control valve
Clicking sound should be heard.
Revision: 2010 May2011 QX56

P0448 EVAP CANISTER VENT CONTROL VALVEEC-329
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0448 EVAP CANISTER VENT CONTROL VALVE
DTC LogicINFOID:0000000006288313
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. Turn ignition switch ON and wait at least 5 seconds.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and let it idle for at least 1 minute.
4. Repeat next procedures 3 times.
- Increase the engine speed up to between 3,000 and 3,500 rpm and maintain that speed for 2 minutes and
50 seconds to 3 minutes.
Do not exceed 3 minutes.
- Fully released accelerator pedal and keep engine idle for approximately 5 seconds.
5. Repeat next procedure 20 times.
- Quickly increase the engine speed up to between 4,000 and 4,500 rpm and maintain that speed for 25 to 30 seconds.
- Fully released accelerator pedal and keep engine idle for at least 35 seconds.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-329, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288314
1.CHECK RUBBER TUBE
1. Turn ignition switch OFF.
2. Disconnect rubber tube connected to EV AP canister vent control valve.
3. Check the rubber tube for clogging.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0448 VENT CONTROL VALVE
(EVAP canister vent control
valve close) EVAP canister vent control valve remains
closed under specified driving conditions.  EVAP canister vent control valve
 EVAP control system pressure sensor
and the circuit
 Blocked rubber tube to EVAP canister vent control valve
 EVAP canister is saturated with water
JMBIA1516GB
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