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M/T

DTC P0446 - EVAPORATIVE EMISSION CONTROL SYSTEM VENT CONTROL LOW INPUT

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.

Wiring Diagram:





WIRING DIAGRAM

10AK1: CHECK OUTPUT SIGNAL FROM ECM.

1. Turn ignition switch to ON.

Connector & Terminal - [(B134) No.10 (+) - Chassis Ground (-)]:





2. Measure voltage between ECM and chassis around.

CHECK: Is the voltage more than 10 V?

YES: Go to step 10AK2.

NO: Go to step 10AK3.

10AK2: CHECK POOR CONTACT.
Check poor contact in ECM connector.

CHECK: Is there poor contact in ECM connector?

YES: Repair poor contact in ECM connector.

NO: Even if MIL lights up, the circuit has returned to a normal condition at this time. (However, the possibility of poor contact still remains.)

NOTE: In this case, repair the following:
- Poor contact in drain valve connector
- Poor contact in ECM connector
- Poor contact in coupling connectors (B97 and B99)

10AK3: CHECK HARNESS BETWEEN DRAIN VALVE AND ECM CONNECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connectors from drain valve and ECM.

Connector & Terminal - [(R69) No.2 - Chassis Ground]:





3. Measure resistance of harness between drain valve connector and chassis ground.

CHECK: Is the resistance less than 10 Ohms?

YES: Repair ground short circuit in harness between ECM and drain valve connector.

NO: Go to step 10AK4.

10AK4: CHECK HARNESS BETWEEN DRAIN VALVE AND ECM CONNECTOR.

Connector & Terminal - [(B134) No.10 - (R69) No.2]:





Measure resistance of harness between ECM and drain valve connector.

CHECK: Is the voltage less than 1 Ohm?

YES: Go to step 10AK5.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and drain valve connector
- Poor contact in coupling connectors (B99)

10AK5: CHECK DRAIN VALVE.

Terminals - [No.1 - No.2]:





Measure resistance between drain valve terminals.

CHECK: Is the resistance between 10 and 100

YES: Go to step 10AK6.

NO: Replace drain valve.

10AK6: CHECK POWER SUPPLY TO DRAIN VALVE.
1. Turn ignition switch to ON.

Connector & Terminals - [(R69) No.1 (+) - Chassis Ground (-)]:





2. Measure voltage between drain valve and chassis ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 10AK7.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between main relay and drain valve
- Poor contact in coupling connectors (B97)
- Poor contact in main relay connector

10AK7: CHECK POOR CONTACT.
Check poor contact in drain valve connector.

CHECK: Is there poor contact in drain valve connector?

YES: Repair poor contact in drain valve connector.

NO: Contact with Subaru of America (SOA) service.

NOTE: Inspection by Subaru of America's DTM is required, because probable cause is deterioration of multiple parts.