DTC P0047: Turbocharger/Supercharger Boost Control "A" Circuit Low: Notes

1. - 

   DTC detecting condition: 

   Immediately at fault recognition

Wiring diagram: 

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK HARNESS BETWEEN ECM AND ELECTRONIC WASTEGATE VALVE CONNECTOR (SHORT TO POWER SUPPLY 
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from ECM.
   3. Disconnect the connector from electronic wastegate valve.
   4. Turn the ignition switch to ON.
   5. Measure the voltage between ECM connector and engine ground.

   Connector & terminal 

   (E159) No. 18 (+) - Engine ground (-):

   (E159) No. 26 (+) - Engine ground (-):

   Is the voltage 5 V or more?

   Yes:  Repair the power supply short circuit of harness between ECM connector and electronic wastegate valve connector.

   No:  Go to 2

2. CHECK HARNESS BETWEEN ECM AND ELECTRONIC WASTEGATE VALVE CONNECTOR (SHORT TO GROUND) 
   1. Turn the ignition switch to OFF.
   2. Measure the resistance between the ECM connector and engine ground.

   Connector & terminal 

   (E159) No. 18 (+) - Engine ground (-):

   (E159) No. 26 (+) - Engine ground (-):

   Is the resistance 1 MΩ or more?

   Yes:  Go to 3

   No:  Repair the ground short circuit of harness between ECM connector and electronic wastegate valve connector.

3. CHECK FOR POOR CONTACT 

   Check for poor contact in ECM and electronic wastegate valve connector.

   Is there poor contact in ECM or electronic wastegate valve connector?

   Yes:  Repair the poor contact of ECM or electronic wastegate valve connector.

   No:  Replace the turbocharger. Ref. to INTAKE (INDUCTION) (H4DOTC)>TURBOCHARGER

   NOTE: The electronic air by-pass valve and the electronic wastegate valve cannot be disassembled.