P1423

2UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P1422,P1423: Fuel Tank Small Leak
P1423 - Fuel Tank Gross Leak

DTC SUMMARY

DESCRIPTION

Refer to the EVAP System EVAP System.

MONITOR DESCRIPTION

1. P1422: Fuel tank small leak

In operation G, the leak detection pump creates negative pressure (vacuum) in the fuel tank and the fuel tank pressure is measured. If the stabilized system pressure is higher than the third reference pressure, the ECM determines that the fuel tank has a small leakage. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

2. P1423: Fuel tank gross leak

In operation G, the leak detection pump creates negative pressure (vacuum) in the fuel tank and the fuel tank pressure is measured. If the stabilized system pressure is higher than [third reference pressure x 0.2] (near atmospheric pressure), the ECM determines that the fuel tank has a large leakage. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

Key-off monitor sequence 1 to 15

1. Atmospheric pressure measurement

2. First reference pressure measurement

3. Vent valve stuck closed check

4. Vacuum introduction for canister

5. Purge VSV stuck closed check

6. Second reference pressure measurement

7. Canister leak

8. Fuel vapor-containment valve (FVCV stuck closed check)

9. Vacuum introduction for fuel tank

10. FVCV stuck closed check

11. FTP sensor stuck check

12 Third reference pressure measurement

13. Fuel tank leak check

14. FTP sensor stuck check

15. Atmospheric pressure measurement

HINT
"Saturated" indicates that the EVAP pressure change in less than 0.12 kPa (0.9 mmHg) in 30 seconds.

TYPICAL MALFUNCTION THRESHOLDS

P1423: Fuel tank gross leak:

P1422: Fuel tank small leak:

MONITOR RESULT

Refer to CHECKING MONITOR STATUS Mode 6 Data.

WIRING DIAGRAM

Refer to the EVAP System EVAP System.

INSPECTION PROCEDURE

Refer to the EVAP System EVAP System.