Infiniti QX56 (JA60). Manual - part 396

EC-236

< COMPONENT DIAGNOSIS >

[VK56DE]

P0447 EVAP CANISTER VENT CONTROL VALVE

Check the following.

• Harness connectors E41, C1

• Harness for open or short between EVAP canister vent control valve and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

7.

CHECK RUBBER TUBE FOR CLOGGING

1. Disconnect rubber tube connected to EVAP canister vent control valve.

2. Check the rubber tube for clogging.
OK or NG

OK

>> GO TO 8.

NG

>> Clean the rubber tube using an air blower.

8.

CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to 

EC-236, "Component Inspection"

.

OK or NG

OK

>> GO TO 9.

NG

>> Replace EVAP canister vent control valve.

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-35, "How to Check Terminal"

 and 

GI-38, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000005149256

EVAP CANISTER VENT CONTROL VALVE

 With CONSULT-III

1. Remove EVAP canister vent control valve from EVAP canister.
2. Check portion B  of EVAP canister vent control valve for being

rusted.

If NG, replace EVAP canister vent control valve.

If OK, go to next step.

3. Reconnect harness connectors disconnected.
4. Turn ignition switch ON.

5. Perform “VENT CONTROL/V” in “ACTIVE TEST” mode.
6. Check air passage continuity and operation delay time.

Make sure new O-ring is installed properly.

Operation takes less than 1 second.

If NG, replace EVAP canister vent control valve.

If OK, go to next step.

7. Clean the air passage (portion A to B) of EVAP canister vent control valve using an air blower.
8. Perform step 6 again.

 Without CONSULT-III

PBIB1033E

Condition VENT CONTROL/V

Air passage continuity between A and B

ON

No

OFF

Yes

P0447 EVAP CANISTER VENT CONTROL VALVE

EC-237

< COMPONENT DIAGNOSIS >

[VK56DE]

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1. Remove EVAP canister vent control valve from EVAP canister.
2. Check portion B  of EVAP canister vent control valve for being

rusted.

3. Check air passage continuity and operation delay time under the

following conditions.

Make sure new O-ring is installed properly.

Operation takes less than 1 second.

If NG, replace EVAP canister vent control valve.

If OK, go to next step.

4. Clean the air passage (portion A to B) of EVAP canister vent control valve using an air blower.
5. Perform step 3 again.

PBIB1033E

Condition

Air passage continuity between A and B

12V direct current supply between
 terminals 1 and 2

No

OFF

Yes

PBIB1034E

EC-238

< COMPONENT DIAGNOSIS >

[VK56DE]

P0448 EVAP CANISTER VENT CONTROL VALVE

P0448 EVAP CANISTER VENT CONTROL VALVE

Component Description

INFOID:0000000005149257

The EVAP canister vent control valve is located on the EVAP canis-

ter and is used to seal the canister vent.

This solenoid valve responds to signals from the ECM. When the

ECM sends an ON signal, the coil in the solenoid valve is energized.

A plunger will then move to seal the canister vent. The ability to seal

the vent is necessary for the on board diagnosis of other evaporative

emission control system components.

This solenoid valve is used only for diagnosis, and usually remains

opened.

When the vent is closed, under normal purge conditions, the evapo-

rative emission control system is depressurized and allows EVAP

Control System diagnosis.

On Board Diagnosis Logic

INFOID:0000000005149258

DTC Confirmation Procedure

INFOID:0000000005149259

1. If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting the next step.

a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c.

Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON and wait at least 5 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and let it idle for at least 1 minute. 
5. Repeat next procedures 3 times.
a. Increase the engine speed up to 3,000 to 3,500 rpm and keep it for 2 minutes and 50 seconds to 3 min-

utes.

Never exceed 3 minutes.

b. Fully released accelerator pedal and keep engine idle for about 5 seconds.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to 

EC-239, "Diagnosis Procedure"

.

If 1st trip DTC is not detected, go to the next step.

8. Repeat next procedure 20 times.

PBIB1263E

BBIA0443E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0448
0448

EVAP canister vent con-
trol 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

P0448 EVAP CANISTER VENT CONTROL VALVE

EC-239

< COMPONENT DIAGNOSIS >

[VK56DE]

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a. Quickly increase the engine speed up to 4,000 to 4,500 rpm or more and keep it for 25 to 30 seconds.
b. Fully released accelerator pedal and keep engine idle for at least 35 seconds.

9. Check 1st trip DTC.
10. If 1st trip DTC is detected, go to 

EC-239, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000005149260

1.

CHECK RUBBER TUBE

1. Turn ignition switch OFF.

2. Disconnect rubber tube connected to EVAP canister vent control valve.

3. Check the rubber tube for clogging.
OK or NG

OK

>> GO TO 2.

NG

>> Clean rubber tube using an air blower.

2.

CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to 

EC-240, "Component Inspection"

.

OK or NG

OK

>> GO TO 3.

NG

>> Replace EVAP canister vent control valve.

3.

CHECK IF EVAP CANISTER SATURATED WITH WATER

1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor

attached.

2. Check if water will drain from the EVAP canister.
Yes or No

Yes

>> GO TO 4.

No

>> GO TO 6.

4.

CHECK EVAP CANISTER

PBIB0972E

BBIA0443E

BBIA0351E