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P0443

AI: DTC P0443 - EVAPORATIVE EMISSION CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT LOW INPUT

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

TROUBLE SYMPTOM:
- Erroneous idling.

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





WIRING DIAGRAM

10AI1: CHECK OUTPUT SIGNAL FROM ECM.
1. Turn ignition switch to ON.

Connector & Terminal (B134) No.2 (+) - Chassis ground (-):




2. Measure voltage between ECM and chassis ground.

CHECK: Is the voltage more than 10 V?

YES: Even if MIL lights up, the circuit has returned to a normal condition at this time. 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.

NO: Go to step 10AI2.

10AI2: CHECK HARNESS BETWEEN PURGE CONTROL SOLENOID VALVE AND ECM CONNECTOR.
1. Turn ignition switch to OFF.
2. Disconnect connectors from purge control solenoid valve and ECM.

Connector & Terminal (E4) No.2 - Engine ground:




3. Measure resistance of harness between purge control solenoid valve connector and engine ground.

CHECK: Is the resistance less than 10 ohm?

YES: Repair ground short circuit in harness between ECM and purge control solenoid valve connector.

NO: Go to step 10AI3.

10AI3: CHECK HARNESS BETWEEN PURGE CONTROL SOLENOID VALVE AND ECM CONNECTOR.

Connector & Terminal (B134) No.2 - (E4) No.2:




Measure resistance of harness between ECM and purge control solenoid valve of harness connector.

CHECK: Is the resistance less than 1 ohm?

YES: Go to step 10AI4.

NO: Repair open circuit in harness between ECM and purge control solenoid valve connector.

NOTE:
In this case, repair the following:
- Open circuit in harness between ECM and purge control solenoid valve connector
- Poor contact in coupling connector (B21)

10AI4: CHECK PURGE CONTROL SOLENOID VALVE.
1. Remove purge control solenoid valve.

Terminals No.1 - No.2:




2. Measure resistance between purge control solenoid valve terminals.

CHECK: Is the resistance between 10 and 100 Kohm?

YES: Go to step 10AI5.

NO: Replace purge control solenoid valve.

10AI5: CHECK POWER SUPPLY TO PURGE CONTROL SOLENOID VALVE.
1. Turn ignition switch to ON.

Connector & Terminal (E4) No.1 (+) - Engine ground (-):




2. Measure voltage between purge control solenoid valve and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 10AI6.

NO: Repair open circuit in harness between main relay and purge control solenoid valve connector.

10AI6: CHECK POOR CONTACT.
Check poor contact in purge control solenoid valve connector.

CHECK: Is there poor contact in purge control solenoid valve connector?

YES: Repair poor contact in purge control solenoid 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.