Nissan Frontier D22. Manual - part 640

DTC P1448 EVAP CANISTER VENT CONTROL VALVE

EC-1663

[VG33ER]

C

D

E

F

G

H

I

J

K

L

M

A

EC

Specification data are reference values and are measured between each terminal and ground.

CAUTION:

Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than the ECM terminals, such as the ground.

Diagnostic Procedure

UBS00E1I

1. 

CHECK RUBBER TUBE

1.

Turn ignition switch OFF.

2.

Check obstructed rubber tube connected to EVAP canister vent
control valve.

OK or NG

 OK

>> GO TO 2.

NG

>> Clean, repair or replace rubber tube.

2. 

CHECK WATER SEPARATOR

1.

Check visually for insect nests in the water separator air inlet.

2.

Check visually for cracks or flaws in the appearance.

3.

Check visually for cracks or flaws in the hose.

4.

Check that A  and C  are not clogged by blowing air into B  with
A , and then C  plugged.

5.

In case of NG in items 2 - 4, replace the parts.

NOTE:

●

Do not disassemble water separator.

OK or NG

 OK

>> GO TO 3.

NG

>> Replace water separator.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

108

R/G

EVAP canister vent control 
valve

 [Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

SEF143S

PBIB1032E

EC-1664

[VG33ER]

DTC P1448 EVAP CANISTER VENT CONTROL VALVE

3. 

CHECK EVAP CANISTER VENT CONTROL VALVE AND O-RING

 With CONSULT-II

1.

Perform “VENT CONTROL/V” in “ACTIVE TEST” mode.

2.

Check air passage continuity and operation delay time.

Operation takes less than 1 second.

 Without CONSULT-II 

1.

Check air passage continuity and operation delay time under the
following condition.

Operation takes less than 1 second.

If NG or operation takes more than 1 second, clean valve using air
blower or replace as necessary.
If portion B  is rusted, replace control valve.
Make sure new O-ring is installed properly.
OK or NG

OK

>> GO TO 4.

NG

>> Replace EVAP canister vent control valve and O-ring.

4. 

CHECK VACUUM CUT VALVE

Check vacuum cut valve as follows:

1.

Plug port C  and D  with fingers.

2.

Apply vacuum to port A  and check that there is no suction from
port B .

3.

Apply vacuum to port B  and check that there is suction from
port A .

4.

Blow air in port B  and check that there is a resistance to flow out
of port A .

5.

Open port C  and D .

6.

Blow air in port A  check that air flows freely out of port C .

7.

Blow air in port B  check that air flows freely out of port D .

OK or NG

OK

>> GO TO 5.

NG

>> Replace vacuum cut valve.

Condition VENT CONTROL/V

Air passage continuity between 

A and B

ON

No

OFF

Yes

SEF013Z

Condition

Air passage continuity between A 

and B

12V direct current supply 
between terminals 1 and 2

No

OFF

Yes

BBIA0309E

SEF379Q

DTC P1448 EVAP CANISTER VENT CONTROL VALVE

EC-1665

[VG33ER]

C

D

E

F

G

H

I

J

K

L

M

A

EC

5. 

CHECK IF EVAP CANISTER SATURATED WITH WATER

1.

Remove EVAP canister with EVAP canister vent control valve attached.

2.

Check if water will drain from the EVAP canister.

OK or NG

OK >> GO 

TO 

6.

NG

>> GO TO 8.

6. 

CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve attached.
The weight should be less than 1.8 kg (4.0 lb).

OK or NG

OK

>> GO TO 8.

NG

>> GO TO 7.

7. 

DETECT MALFUNCTIONING PART

Check the following.

●

EVAP canister for damage

●

EVAP hose between EVAP canister and water separator for clogging or poor connection

>> Repair hose or replace EVAP canister.

8. 

CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR HOSE

Check disconnection or improper connection of hose connected to EVAP control system pressure sensor.

OK or NG

OK

>> GO TO 9.

NG

>> Repair it.

9. 

CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR

1.

Disconnect EVAP control system pressure sensor harness con-
nector.

2.

Check connectors for water.
Water should not exist.

OK or NG

OK

>> GO TO 10.

NG

>> Replace EVAP control system pressure sensor.

SEF596U

AEC651A

EC-1666

[VG33ER]

DTC P1448 EVAP CANISTER VENT CONTROL VALVE

10. 

CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR FUNCTION

Refer to DTC P0452 

EC-1524, "DTC Confirmation Procedure"

  or DTC P0453 

EC-1530, "DTC Confirmation

Procedure"

 .

OK or NG

OK

>> GO TO 11.

NG

>> Replace EVAP control system pressure sensor.

11. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-1297, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END.