DTC P2404: EVAP System Leak Detection Pump Sense Circuit Range/Performance: Notes
DTC detecting condition:
Detected when two consecutive driving cycles with fault occur.
- After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>CLEAR MEMORY MODE>OPERATION , and inspection mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>INSPECTION MODE>PROCEDURE ..
- Use the check board when measuring the ECM terminal voltage and resistance.
Wiring diagram:
Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .
- CHECK DTC.
Read the engine DTC using the Subaru Select Monitor or general scan tool. Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>READ DIAGNOSTIC TROUBLE CODE (DTC) .
Is DTC other than P2404 displayed? (Current malfunction)
Yes: Check the appropriate DTC using the "List of Diagnostic Trouble Code (DTC)". Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .
No: Go to 2.
- CHECK LEAK CHECK VALVE ASSEMBLY PUMP.
Operate the ELCM pump using the Subaru Select Monitor.
NOTE: For detailed operation procedures, refer to the "Active Test". Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>ACTIVE TEST .Does the leak check valve assembly pump operate?
Yes: Go to 6.
No: Go to 3.
- CHECK POWER SUPPLY OF LEAK CHECK VALVE ASSEMBLY.
- Turn the ignition switch to OFF.
- Disconnect the connector from the leak check valve assembly.
- Turn the ignition switch to ON.
- Measure the voltage between the leak check valve assembly connector and chassis ground.
Connector & terminal
(R400) No. 3 (+) - Chassis ground (-):
Is the voltage 10 V or more?
Yes: Go to 4.
No: Repair the harness and connector.
NOTE: In this case, repair the following item:- Open circuit in harness between the main relay and the leak check valve assembly connector
- Poor contact of main relay connector
- Poor contact of coupling connector
- CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR.
- Turn the ignition switch to OFF.
- Disconnect the connector from ECM.
- Measure the resistance of harness between ECM connector and the leak check valve assembly connector.
Connector & terminal
(B134) No. 3 - (R400) No. 4:
Is the resistance less than 1 Ω?
Yes: Go to 5.
No: Repair the harness and connector.
NOTE: In this case, repair the following item:- Open circuit in harness between ECM connector and the leak check valve assembly connector
- Poor contact of coupling connector
- CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR.
- Measure the resistance of harness between ECM connector and chassis ground.
Connector & terminal
(B134) No. 3 - Chassis ground:
Is the resistance 1 MΩ or more?
Yes: Replace the leak check valve assembly. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (EXCEPT FOR STI)>LEAK CHECK VALVE ASSEMBLY .
No: Repair the short circuit to ground in harness between ECM connector and leak check valve assembly connector.
- Measure the resistance of harness between ECM connector and chassis ground.
- CHECK LEAK CHECK VALVE ASSEMBLY SWITCHING VALVE.
Using the Subaru Select Monitor, operate the leak check valve assembly switching valve.
NOTE: For detailed operation procedures, refer to the "Active Test". Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>ACTIVE TEST .Does the leak check valve assembly switching valve operate?
Yes: Go to 10.
No: Go to 7.
- CHECK POWER SUPPLY OF LEAK CHECK VALVE ASSEMBLY.
- Turn the ignition switch to OFF.
- Disconnect the connector from the leak check valve assembly.
- Turn the ignition switch to ON.
- Measure the voltage between the leak check valve assembly connector and chassis ground.
Connector & terminal
(R400) No. 5 (+) - Chassis ground (-):
Is the voltage 10 V or more?
Yes: Go to 8.
No: Repair the harness and connector.
NOTE: In this case, repair the following item:- Open circuit in harness between the main relay and the leak check valve assembly connector
- Poor contact of main relay connector
- Poor contact of coupling connector
- CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR.
- Turn the ignition switch to OFF.
- Disconnect the connector from ECM.
- Measure the resistance of harness between ECM connector and the leak check valve assembly connector.
Connector & terminal
(B134) No. 27 - (R400) No. 1:
Is the resistance less than 1 Ω?
Yes: Go to 9.
No: Repair the harness and connector.
NOTE: In this case, repair the following item:- Open circuit in harness between ECM connector and the leak check valve assembly connector
- Poor contact of coupling connector
- CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR.
- Measure the resistance of harness between ECM connector and chassis ground.
Connector & terminal
(B134) No. 27 - Chassis ground:
Is the resistance 1 MΩ or more?
Yes: Replace the leak check valve assembly. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (EXCEPT FOR STI)>LEAK CHECK VALVE ASSEMBLY .
No: Repair the short circuit to ground in harness between ECM connector and leak check valve assembly connector.
- Measure the resistance of harness between ECM connector and chassis ground.
- CHECK EVAPORATIVE EMISSION CONTROL SYSTEM.
Perform drive cycle I. Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>DRIVE CYCLE>PROCEDURE>DRIVE CYCLE I .
Is DTC P2404 displayed? (Current malfunction)
Yes: Replace the leak check valve assembly. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (EXCEPT FOR STI)>LEAK CHECK VALVE ASSEMBLY .
No: Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.
NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.