2009 INFINITI QX56 engine

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
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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

P0453 EVAP CONTROL SYSTEM PRESSURE SENSOREC-245
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P0453 EVAP CONTROL SYSTEM
PRESSURE SENSOR
Component DescriptionINFOID:0000000003771515
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:0000000003771516
NOTE:
If DTC P0453 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-285
.
DTC Confirmation ProcedureINFOID:0000000003771517
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.
BBIA0443E
PBIB1207E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0453
0453 EVAP control system pressure
sensor high input An excessively high voltage from the
sensor is sent to ECM.  Harness or connectors
(The sensor circuit is open or shorted.)
 EVAP control system pressure sensor
 EVAP canister vent control valve
 EVAP canister
 Rubber hose from EVAP canister vent
control valve to vehicle frame
Revision: December 20092009 QX56

EC-246
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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

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-254
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P0455 EVAP CONTROL SYSTEM
2. Apply 12 volts DC to EVAP canister vent control va
lve. The valve will close. (Continue to apply 12 volts
until the end of test.)
3. Pressurize the EVAP line using pressure pump with 1.3 to 2.7 kPa (10 to 20 mmHg, 0.39 to 0.79 inHg),
then remove pump and EVAP service port adapter.
CAUTION:
 Do not use compressed air or a high pressure pump.
 Do not exceed 4.12 kPa (0.042 kg/cm
2, 0.6 psi) of pressure in the system.
4. Using EVAP leak detector, locate the EVAP leak. For the leak
detector, refer to the instruction manual for more details. Refer
to EC-37, "Description"
.
OK or NG
OK >> GO TO 12.
NG >> Repair or replace.
11 .CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
With CONSULT-III
1. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at EVAP service port.
2. Start engine.
3. Perform “PURG VOL CONT/V ” in “ACTIVE TEST” mode.
4. Touch “Qu” on CONSULT-III screen to increase “PURG VOL CONT/V” opening to 100%.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
OK or NG
OK >> GO TO 14.
NG >> GO TO 13.
12.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
Without CONSULT-II I
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13.CHECK VACUUM HOSE
Check vacuum hoses for clogging or disconnection. Refer to EC-37, "Description"
.
OK or NG
BBIA0443E
SEF200U
Vacuum should exist.
Vacuum should exist.
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

EC-258
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P0456 EVAP CONTROL SYSTEM
DTC Confirmation Procedure
INFOID:0000000003771525
NOTE:
 If DTC P0456 is displayed with P0442, firs t perform trouble diagnosis for DTC P0456.
 After repair, make sure that the hoses and clips are installed properly.
 If DTC Confirmation Procedure has been previously conducted, 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:
 Open engine hood before conducting following procedure.
 If any of following conditions are met just befo re the DTC confirmation procedure, leave the vehicle
for more than 1 hour.
- Fuel filler cap is removed.
- Fuel is refilled or drained.
- EVAP component parts is/are removed.
 Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Make sure the following conditions are met.
FUEL LEVEL SE: 0.25 - 1.4V
COOLAN TEMP/S: 0 - 32 °C (32 - 90 °F)
FUEL T/TMP SE: 0 - 35 °C (32 - 95 °F)
INT/A TEMP SE: More than 0 °C (32 °F)
If NG, turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle) or refilling/draining
fuel until the output voltage condition of the “FUE L LEVEL SE” meets within the range above and leave
the vehicle for more than 1 hour. Then start from step 1).
3. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
4. Select “EVP V/S LEAK P0456/P1456” of “EVAPO RATIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-III.
Follow the instruction displayed.
5. Make sure that “OK” is displayed. If “NG” is displayed, refer to EC-259, "Diagnosis Procedure"
.
NOTE:
 If the engine speed cannot be maintained with in the range displayed on CONSULT-III screen, go
to EC-13, "Basic Inspection"
.
 Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid
valve properly.
Overall Function CheckINFOID:0000000003771526
WITH GST
Use this procedure to check the overall function of the EV AP very small leak function. During this check, a 1st
trip DTC might not be confirmed.
CAUTION:
 Do not use compressed air, doing so may damage the EVAP system.
 Do not start engine.
 Do not exceeded 4.12 kPa (0.042 kg/cm
2 , 0.6 psi).
Revision: December 20092009 QX56