2009 INFINITI QX56 fuel

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VALVE
EC-227
< COMPONENT DIAGNOSIS > [VK56DE]
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P0444, P0445 EVAP CANISTER PURG
E VOLUME CONTROL SOLENOID
VA LV E
DescriptionINFOID:0000000003771490
SYSTEM DESCRIPTION
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
This system controls flow rate of fuel vapor from the EVAP canister. The opening of the vapor by-pass pas-
sage in the EVAP canister purge volume control solenoid valve changes to control the flow rate. The EVAP
canister purge volume control solenoid valve repeats ON/O FF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engi ne control. The optimum value stored in the ECM is
determined by considering various engine conditions. When t he engine is operating, the flow rate of fuel vapor
from the EVAP canister is regulated as the air flow changes.
COMPONENT DESCRIPTION
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.
On Board Diagnosis LogicINFOID:0000000003771491
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
EVAP canister
purge flow controlEVAP canister purge vol-
ume control solenoid valve
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Air fuel ratio (A/F) sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Wheel sensor Vehicle speed*
2
PBIB2057E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0444
0444 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 so-
lenoid valve
P0445
0445 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 so-
lenoid valve
Revision: December 20092009 QX56

P0452 EVAP CONTROL SYSTEM PRESSURE SENSOREC-241
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P0452 EVAP CONTROL SYSTEM
PRESSURE SENSOR
Component DescriptionINFOID:0000000003771510
The EVAP control system pressure sens or detects pressure in the purge line. The sensor output voltage to the
ECM increases as pressure increases.
On Board Diagnosis LogicINFOID:0000000003771511
NOTE:
If DTC P0452 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-285
.
DTC Confirmation ProcedureINFOID:0000000003771512
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Always perform test at a temperature of 5 °C (41 °F) or more.
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. Select “DATA MONITOR” mode with CONSULT-III.
5. Make sure that “FUEL T/TMP SE” is more than 0 °C (32 °F).
BBIA0443E
PBIB1207E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0452
0452 EVAP control system pressure
sensor low input An excessively low voltage from the sen-
sor is sent to ECM.  Harness or connectors
(The sensor circuit is open or shorted.)
 EVAP control system pressure sensor
Revision: December 20092009 QX56

EC-242
< COMPONENT DIAGNOSIS >[VK56DE]
P0452 EVAP CONTROL S
YSTEM PRESSURE SENSOR
6. Start engine and wait at least 20 seconds.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-242, "Diagnosis Procedure"
.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Check that voltage between ECM terminal 107 (Fuel tank tem-
perature sensor signal) and ground is less than 4.2V.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and wait at least 20 seconds.
5. Select Service $07 with GST. If 1st trip DTC is detected, go to EC-242, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771513
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "Ground Inspection"
.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check sensor harness connector for water.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace harness connector.
PBIB1110E
BBIA0354E
Water should not exist.
BBIA0443E
Revision: December 20092009 QX56

EC-246
< COMPONENT DIAGNOSIS >[VK56DE]
P0453 EVAP CONTROL S
YSTEM PRESSURE SENSOR
3. Turn ignition switch ON.
4. Select “DATA MONITOR” mode with CONSULT-III.
5. Make sure that “FUEL T/TMP SE” is more than 0°C (32 °F).
6. Start engine and wait at least 20 seconds.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-246, "Diagnosis Procedure"
.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Check that voltage between ECM terminal 107 (Fuel tank tem-
perature sensor signal) and ground is less than 4.2V.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and wait at least 20 seconds.
5. Select Service $07 with GST. If 1st trip DTC is detected, go to EC-246, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771518
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "Ground Inspection"
.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check sensor harness connector for water.
OK or NG
PBIB1110E
BBIA0354E
Water should not exist.
BBIA0443E
Revision: December 20092009 QX56

EC-250
< COMPONENT DIAGNOSIS >[VK56DE]
P0455 EVAP CONTROL SYSTEM
P0455 EVAP CONTROL SYSTEM
On Board Diagn
osis LogicINFOID:0000000003771520
This diagnosis detects a very large leak (fuel filler c ap fell off etc.) in EVAP system between the fuel tank and
EVAP canister purge volume control solenoid valve.
CAUTION:
 Use only a genuine NISSAN fuel filler cap as a replacemen t. If an incorrect fuel filler cap is used, the
MIL may come on.
 If the fuel filler cap is not tigh tened properly, the MIL may come on.
 Use only a genuine NISSAN rubber tube as a replacement.
DTC Confirmation ProcedureINFOID:0000000003771521
CAUTION:
Never remove fuel filler cap during the DTC Confirmation Procedure.
NOTE:
PBIB1026E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0455
0455 EVAP control system
gross leak detected EVAP control system has a very large leak
such as fuel filler cap fell off, EVAP control
system does not operate properly.  Fuel filler cap remains open or fails to close.
 Incorrect fuel tank vacuum relief valve
 Incorrect fuel filler cap used
 Foreign matter caught in fuel filler cap.
 Leak is in line between intake manifold and
EVAP canister purge volume control sole-
noid valve.
 Foreign matter caught in EVAP canister vent control valve.
 EVAP canister or fuel tank leaks
 EVAP purge line (pipe and rubber tube)
leaks
 EVAP purge line rubber tube bent.
 Loose or disconnected rubber tube
 EVAP canister vent control valve and the cir- cuit
 EVAP canister purge volume control sole- noid valve and the circuit
 Fuel tank temperature sensor
 O-ring of EVAP canister vent control valve is
missing or damaged.
 EVAP control system pressure sensor
 Refueling EVAP vapor cut valve
 ORVR system leaks
Revision: December 20092009 QX56

P0455 EVAP CONTROL SYSTEMEC-251
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Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve
properly.
 If DTC Confirmation Procedure has been previously c onducted, always perform the following before con-
ducting the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
 Perform “DTC WORK SUPPORT” when the fuel level is between 1/4 and 3/4 full, and vehicle is placed
on flat level surface.
 Open engine hood before conducting the following procedures.
WITH CONSULT-III
1. Tighten fuel filler cap securely until ratcheting sound is heard.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
5. Make sure that the following conditions are met.
COOLAN TEMP/S: 0 - 70 °C (32 - 158 °F)
INT/A TEMP SE: 0 - 60 °C (32 - 140 °F)
6. Select “EVP SML LEAK P0442/P1442” of “EVAPO RATIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on the CONSULT-III screen, go to
EC-13, "Basic Inspection"
.
7. Make sure that “OK” is displayed. If “NG” is displayed, select “SELF-DIAG R ESULTS” mode and make sure that “EVAP GROSS LEAK
[P0455]” is displayed. If it is displayed, refer to EC-251, "Diagnosis Procedure"
.
If P0442 is displayed, perform Diagnostic Procedure for DTC P0442, EC-216, "Diagnosis Procedure"
.
WITH GST
NOTE:
Be sure to read the explanation of EC-456, "DTC Index"
before driving vehicle.
1. Start engine.
2. Drive vehicle according to EC-456, "DTC Index"
.
3. Stop vehicle.
4. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
5. Select Service $07 with GST.  If P0441 is displayed on the screen, go to EC-211, "Diagnosis Procedure"
.
 If P0442 is displayed on the screen, go to EC-216, "Diagnosis Procedure"
.
 If P0455 is displayed on the screen, go to EC-251, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771522
1.CHECK FUEL FILLER CAP DESIGN
1. Turn ignition switch OFF.
Revision: December 20092009 QX56

EC-252
< COMPONENT DIAGNOSIS >[VK56DE]
P0455 EVAP CONTROL SYSTEM
2. Check for genuine NISSAN fuel filler cap design.
OK or NG
OK >> GO TO 2.
NG >> Replace with genuine NISSAN fuel filler cap.
2.CHECK FUEL FILLER CAP INSTALLATION
Check that the cap is tightened proper ly by rotating the cap clockwise.
OK or NG
OK >> GO TO 3.
NG >> 1. Open fuel filler cap, then clean cap and fuel filler neck threads using air blower.
2. Retighten until ratcheting sound is heard.
3.CHECK FUEL FILLER CAP FUNCTION
Check for air releasing sound while opening the fuel filler cap.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-264, "Component Inspection"
.
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
5.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks, improper connection or
disconnection.
Refer to EC-37, "Description"
.
OK or NG
OK >> GO TO 6.
NG >> Repair or reconnect the hose.
6.CLEAN EVAP PURGE LINE
Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 7.
7.CHECK EVAP CANISTER VENT CONTROL VALVE
Check the following.
 EVAP canister vent control valve is installed properly. Refer to EC-491, "Removal and Installation"
.
 EVAP canister vent control valve. Refer to EC-232, "Component Inspection"
.
OK or NG
OK >> GO TO 8.
NG >> Repair or replace EVAP cani ster vent control valve and O-ring.
8.INSTALL THE PRESSURE PUMP
SEF915U
Revision: December 20092009 QX56

P0455 EVAP CONTROL SYSTEMEC-255
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OK (With CONSULT-III)>>GO TO 14.
OK (Without CONSULT-III)>>GO TO 15.
NG >> Repair or reconnect the hose.
14.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-III
1. Start engine.
2. Perform “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-III. Check that engine speed var-
ies according to the valve opening.
OK or NG
OK >> GO TO 16.
NG >> GO TO 15.
15.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Refer to EC-229, "Component Inspection"
.
OK or NG
OK >> GO TO 16.
NG >> Replace EVAP canister purge volume control solenoid valve.
16.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-181, "Component Inspection"
.
OK or NG
OK >> GO TO 17.
NG >> Replace fuel level sensor unit.
17.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-239, "Component Inspection"
.
OK or NG
OK >> GO TO 18.
NG >> Replace EVAP control system pressure sensor.
18.CHECK EVAP/ORVR LINE
Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper con-
nection. For location, refer to EC-409
.
OK or NG
OK >> GO TO 19.
NG >> Repair or replace hoses and tubes.
19.CHECK RECIRCULATION LINE
Check recirculation line between filler neck tube and fuel tank for clogging, kink, cracks, looseness and
improper connection.
OK or NG
OK >> GO TO 20.
NG >> Repair or replace hose, tube or filler neck tube.
20.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-411, "Component Inspection"
.
OK or NG
OK >> GO TO 21.
NG >> Replace refueling EVAP vapor cut valve with fuel tank.
21.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Revision: December 20092009 QX56