Nissan Maxima. Manual - part 464

EC-340

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0448 EVAP CANISTER VENT CONTROL VALVE

YES

>> GO TO 7.

NO

>> GO TO 6.

6.

DETECT MALFUNCTIONING PART

Check the following.

• EVAP canister for damage

• EVAP hose between EVAP canister and drain filter for clogging or poor connection

>> Repair hose or replace EVAP canister. Refer to 

FL-14, "Removal and Installation (EVAP Canis-

ter)"

.

7.

CHECK EVAP CONTROL 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 8.

NO

>> Replace EVAP control system pressure sensor. Refer to 

FL-17, "Removal and Installation"

.

8.

CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to 

EC-340, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace EVAP control system pressure sensor. Refer to 

FL-17, "Removal and Installation"

.

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-41, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000010095023

EVAP CANISTER VENT CONTROL VALVE

1.

CHECK EVAP CANISTER VENT CONTROL VALVE-I

1. Remove EVAP canister vent control valve from EVAP canister. Refer to 

FL-16, "Removal and Installation"

.

2. Check portion (A) of EVAP canister vent control valve for rust.
Is it rusted?

YES

>> Replace EVAP canister vent control valve. Refer to 

FL-

16, "Removal and Installation"

.

NO

>> GO TO 2.

2.

CHECK EVAP CANISTER VENT CONTROL VALVE-II

With CONSULT

1. Reconnect harness connectors disconnected.

2. Turn ignition switch ON.

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

JMBIA0168ZZ

P0448 EVAP CANISTER VENT CONTROL VALVE

EC-341

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4. Check air passage continuity and operation delay time.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Without CONSULT

1. Disconnect EVAP canister vent control valve harness connector.

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

following conditions.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 3.

3.

CHECK EVAP CANISTER VENT CONTROL VALVE

With CONSULT

1. Clean the air passage [portion (A) to (B)] of EVAP canister vent control valve using an air blower.

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

3. Check air passage continuity and operation delay time.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Without CONSULT

1. Clean the air passage [portion (A) to (B)] of EVAP canister vent

control valve using an air blower.

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

following conditions.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace EVAP canister vent control valve. Refer to 

FL-16, "Removal and Installation"

.

DRAIN FILTER

1. Check visually for insect nests in the drain filter air inlet.
2. Check visually for cracks or flaws in the appearance.
3. Check visually for cracks or flaws in the hose.

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

Condition

Air passage continuity between (A) and (B)

12 V direct current supply between
 terminals 1 and 2

Not existed

OFF

Existed

JMBIA0169ZZ

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

No

OFF

Yes

Condition

Air passage continuity between (A) and (B)

12 V direct current supply between
 terminals (1) and (2)

No

OFF

Yes

JMBIA0169ZZ

EC-342

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0448 EVAP CANISTER VENT CONTROL VALVE

4. Blow air into port A and check that it flows freely out of port B.
5. Block port B.
6. Blow air into port A and check that there is no leakage.
7. If NG, replace drain filter.

PBIB3641E

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

EC-343

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P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

Description

INFOID:0000000010095024

The EVAP control system pressure sensor detects pressure in the

purge line. The sensor output voltage to the ECM increases as pres-

sure increases.

DTC Logic

INFOID:0000000010095025

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

NOTE:

Never remove fuel filler cap during DTC confirmation procedure.

1.

PRECONDITIONING

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

before conducting the next test. 

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.

With CONSULT>>GO TO 2.
Without CONSULT>>GO TO 5.

2.

PERFORM DTC CONFIRMATION PROCEDURE-1

With CONSULT

1. Start engine and let it idle for 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-344, "Diagnosis Procedure"

.

NO

>> GO TO 3.

PBIB3370E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0451

EVAP control system 
pressure sensor perfor-
mance

ECM detects a sloshing signal from the EVAP 
control system pressure sensor

• Harness or connectors

(EVAP control system pressure sensor 
circuit is shorted.)
[Crankshaft position (CKP) sensor (POS) 
circuit is shorted.]
[Accelerator pedal position (APP) sensor 
2 circuit is shorted.]
(Refrigerant pressure sensor circuit is 
shorted.)

• EVAP control system pressure sensor
• CKP sensor (POS)
• APP sensor
• Refrigerant pressure sensor