DTC P1499: Coil 4 EGR "A" Control Circuit High: Notes

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

• Improper idling
• Poor driving performance
• Engine breathing
  CAUTION:

  • After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>Clear Memory Mode>OPERATION , and inspection mode Ref. 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 Ref. to WIRING SYSTEM>Engine Electrical System>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK HARNESS BETWEEN ECM AND EGR CONTROL VALVE CONNECTOR  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from ECM.
   3. Disconnect the connector from the EGR control valve.
   4. Turn the ignition switch to ON.
   5. Measure the voltage between ECM connector and engine ground.

      Connector & terminal 

      DTC P1493; (E159) No. 5 (+) - Engine ground (-):

      DTC P1495; (E159) No. 21 (+) - Engine ground (-):

      DTC P1497; (E159) No. 13 (+) - Engine ground (-):

      DTC P1499; (E159) No. 29 (+) - Engine ground (-):

   Is the voltage 10 V or more?

   Yes: Repair the short circuit to power supply in the harness between the ECM connector and EGR control valve connector.

   No: Go to  2.

2. CHECK EGR CONTROL VALVE  .

   Measure the resistance between EGR control valve terminals.

   Terminals 

   DTC P1493; No. 2 - No. 3:

   DTC P1495; No. 2 - No. 1:

   DTC P1497; No. 5 - No. 4:

   DTC P1499; No. 5 - No. 6:

   Is the resistance 20 Ω or more?

   Yes: Repair the poor contact of ECM connector.

   No: Replace EGR control valve. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (EXCEPT FOR STI)>EGR Control Valve .