DTC Description
DTC DETECTION LOGIC
This diagnosis detects leaks in the EVAP line between fuel tank and EVAP canister purge volume control solenoid valve, using the negative pressure caused by decrease of fuel temperature in the fuel tank after turning ignition switch OFF.
If ECM judges there are no leaks, the diagnosis will be OK.
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
P0456 | EVAP VERY SML LEAK [Evaporative emission system leak detected (very small leak)] |
|
CAUTION:
POSSIBLE CAUSE
FAIL-SAFE
Not applicable
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
Do you have CONSULT? YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE-1
WITH CONSULT
NOTE: It will take at most 2 hours until “OFF” of “EVAP DIAG READY” changes to “ON”.
NOTE: Never turn ignition switch ON during 90 minutes.
Which is displayed on CONSULT? CMPLT>> GO TO 3.
YET >> Perform DTC CONFIRMATION PROCEDURE again. GO TO 1.
3.PERFORM DTC CONFIRMATION PROCEDURE-2
Check 1st trip DTC.
Is 1st trip DTC detected? YES >> Proceed toEC-339, "Diagnosis Procedure".
NO >> INSPECTION END.
4.PERFORM DTC CONFIRMATION PROCEDURE
WITH GST
NOTE: Never turn ignition switch ON during 90 minutes.
Is 1st trip DTC detected? YES >> Proceed to EC-339, "Diagnosis Procedure".
NO >> INSPECTION END.
Diagnosis Procedure
1.CHECK FUEL FILLER CAP DESIGN
Is the inspection result normal? YES >> GO TO 2.
NO >> Replace with genuine NISSAN fuel filler cap.
2.CHECK FUEL FILLER CAP INSTALLATION
Check that the cap is tightened properly by rotating the cap clockwise.
Is the inspection result normal? YES >> GO TO 3.
NO >> Open fuel filler cap, then clean cap and fuel filler neck threads using air blower. Then retighten until reteaching sound is heard.
3.CHECK FUEL FILLER CAP FUNCTION
Check for air releasing sound while opening the fuel filler cap.
Is the inspection result normal? YES >> GO TO 5.
NO >> GO TO 4.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-343, "Component Inspection".
Is the inspection result normal? YES >> GO TO 5.
NO >> Replace fuel filler cap with a genuine one.
5.CHECK FOR EVAP LEAK
Refer to EC-496, "Inspection".
Is there any leak in EVAP line? YES >> Repair or replace.
NO >> GO TO 6.
6.CHECK EVAP CANISTER VENT CONTROL VALVE
Check the following.
Refer to FL-21, "Exploded View".
Refer to FL-21, "Removal and Installation".
Is the inspection result normal? YES >> GO TO 7.
NO >> Repair or replace EVAP canister vent control valve and O-ring. Refer to FL-21, "Removal and Installation".
7.CHECK IF EVAP CANISTER SATURATED WITH WATER
Does water drain from EVAP canister? YES >> GO TO 8.
NO-1 >> With CONSULT: GO TO 10.
NO-2 >> Without CONSULT: GO TO 11.
8.CHECK EVAP CANISTER
Weigh the EVAP canister assembly with the EVAP canister vent control valve and EVAP control system pressure sensor attached. Refer to FL-21, "Removal and Installation".
The weight should be less than 2.1 kg (4.6 lb).
Is the inspection result normal? YES-1 >> With CONSULT: GO TO 10.
YES-2 >> Without CONSULT: GO TO 11.
NO >> GO TO 9.
9.DETECT MALFUNCTIONING PART
Check the following.
>> Repair hose or replace EVAP canister. Refer to FL-19, "Removal and Installation".
10.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
With CONSULT
Vacuum should exist.
Is the inspection result normal? YES >> GO TO 13.
NO >> GO TO 12.
11.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
Without CONSULT
Vacuum should exist.
Is the inspection result normal? YES >> GO TO 13.
NO >> GO TO 12.
12.CHECK VACUUM HOSE
Check vacuum hoses for clogging or disconnection.
Is the inspection result normal?
YES >> GO TO 13.
NO >> Repair or reconnect the hose.
13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Check the EVAP canister purge volume control solenoid valve. Refer to EC-315, "Component Inspection".
Is the inspection result normal? YES >> GO TO 14.
NO >> Replace EVAP canister purge volume control solenoid valve. Refer to EC-14, "Component Parts Location".
14.CHECK FUEL TANK TEMPERATURE SENSOR
Check the fuel tank temperature sensor. Refer to EC-273, "Component Inspection".
Is the inspection result normal? YES >> GO TO 15.
NO >> Replace fuel level sensor unit. Refer to FL-6, "Removal and Installation".
15.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Check the EVAP control system pressure sensor. Refer to FL-22, "Removal and Installation".
Is the inspection result normal? YES >> GO TO 16.
NO >> Replace EVAP control system pressure sensor. Refer to FL-22, "Removal and Installation".
16.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.
Refer to EC-53, "EVAPORATIVE EMISSION SYSTEM : System Description".
Is the inspection result normal? YES >> GO TO 17.
NO >> Repair or reconnect the hose.
17.CLEAN EVAP PURGE LINE
Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 18.
18.CHECK EVAP/ORVR LINE
Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kink, looseness and improper connection.
For location, refer to EC-53, "EVAPORATIVE EMISSION SYSTEM : System Description".
Is the inspection result normal? YES >> GO TO 19.
NO >> Repair or replace hoses and tubes.
19.CHECK RECIRCULATION LINE
Check recirculation line between fuel filler tube and fuel tank for clogging, kink, cracks, looseness and improper connection.
Is the inspection result normal? YES >> GO TO 20.
NO >> Repair or replace hose, tube or fuel filler tube. Refer to FL-12, "FWD : Exploded View" (with FWD models) or FL-16, "AWD : Exploded View" (with AWD models).
20.CHECK REFUELING EVAP VAPOR CUT VALVE
Check the refueling EVAP vapor cut valve. Refer to FL-15, "FWD : Inspection" (with FWD models) or FL-18, "AWD : Inspection" (with AWD models).
Is the inspection result normal? YES >> GO TO 21.
NO >> Replace refueling EVAP vapor cut valve with fuel tank. Refer to FL-12, "FWD : Removal and Installation" (with FWD models) or FL-16, "AWD : Removal and Installation" (with AWD models
21.CHECK FUEL LEVEL SENSOR
Check the fuel level sensor. Refer to MWI-63, "Component Inspection".
Is the inspection result normal? YES >> GO TO 22.
NO >> Replace fuel level sensor unit. Refer to FL-6, "Removal and Installation".
22.CHECK INTERMITTENT INCIDENT
Refer to GI-41, "Intermittent Incident".
>> INSPECTION END
Component Inspection
1.CHECK FUEL FILLER CAP
Pressure: 15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 - 2.90 psi) Vacuum: −6.0 to −3.3 kPa (−0.061 to −0.034 kg/cm2, −0.87 to −0.48 psi)
Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 2.
2.REPLACE FUEL FILLER CAP
Replace fuel filler cap.
CAUTION: Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may illuminate.
>> INSPECTION END
Wiring diagram
ENGINE CONTROL SYSTEM
Wiring Diagram
...
Diagnosis and repair workflow
Work Flow
OVERALL SEQUENCE
DETAILED FLOW
1. OBTAIN INFORMATION ABOUT SYMPTOM
Interview the customer to obtain as much information as possible about the
conditions and environment under
which the malfunction occurred.
>> GO TO 2.
2. CONFIRM THE SYMPTOM
Check the malfunction on the ...
Preparation
Special Service Tool
The actual shape of the tools may differ from those illustrated here.
Tool number
(TechMate No.)
Tool name
Description
—
(J-39570)
Chassis Ear
Locating the noise
—
(J-50397)
NISSAN Squeak and Rattle Kit
...