P2420

3UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2420: Evaporative Emission Pressure Switching Valve Stuck OFF
P2420 - Evaporative Emission Pressure Switching Valve Stuck OFF

DTC SUMMARY





HINT
The vent valve is built into the canister pump module.

DESCRIPTION

The description can be found in the EVAP (Evaporative Emission) System EVAP System.

INSEPCTION PROCEDURE

Refer to the EVAP system EVAP System.

MONITOR DESCRIPTION

5 hours* after the ignition switch is turned OFF, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.

HINT
*: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the ignition switch is turned OFF, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the ignition switch is turned OFF, the monitor check starts 2.5 hours later.





*: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.





P2420: Vent valve stuck open (vent)

In operation C, the vent valve turns ON (closes) and the EVAP system pressure is then measured by the ECM, using the canister pressure sensor, to conduct an EVAP leak check. If the pressure does not increase when the vent valve is open, the ECM interprets this as the vent valve being stuck open. The ECM illuminates the MIL and sets the DTC.





MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





1. Key-off monitor sequence 1 to 8

1. Atmospheric pressure measurement





2. First reference pressure measurement





3. Vent valve stuck closed check





4. Vacuum introduction





5. Purge VSV stuck closed check





6. Second reference pressure measurement





7. Leak check





8. Atmospheric pressure measurement





TYPICAL MALFUNCTION THRESHOLDS





MONITOR RESULT

Refer to the CHECKING MONITOR STATUS Mode 6 Data.

CONFIRMATION DRIVING PATTERN





NOTICE:
- The Evaporative System Check (Automatic Mode) consists of 5 steps performed automatically by the Techstream. It takes a maximum of approximately 19 minutes.
- Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the fuel tank leak check unavailable.
- Do not run the engine during this operation.
- When the temperature of the fuel is 35°C (95°F) or higher, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the fuel temperature below 35°C (95°F).
- Connect the Techstream to the DLC3.

- Turn the ignition switch to ON and turn the Techstream on.

- Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).

- Turn the ignition switch off and wait for at least 30 seconds.

- Turn the ignition switch to ON and turn the Techstream on [A].

- Enter the following menu items: Powertrain / Engine / Utility / Evaporative System Check / Automatic Mode.

- After the "Evaporative System Check" is completed, check All Readiness by entering the following menus: Powertrain / Engine / Utility / All Readiness.

- Input the DTC: P2420.

- Check the DTC judgment result [B].





HINT
If the judgment result shows ABNORMAL, the system has a malfunction.

- If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.