DTC P0606: Control Module Processor: Notes

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

• Improper idling
• Poor driving performance

Wiring diagram: 

Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK INPUT VOLTAGE OF ECM. 
   1. Turn the ignition switch to ON.
   2. Measure the voltage between ECM connector and chassis ground.

   Connector & terminal 

   (B136) No. 1 (+) - Chassis ground (-):

   (B137) No. 7 (+) - Chassis ground (-):

   Is the voltage 10 - 13 V?

   Yes:  Go to  2.

   No:  Repair the open or short to ground in the power supply circuit.

2. CHECK INPUT VOLTAGE OF ECM. 
   1. Start the engine.
   2. Measure the voltage between ECM connector and chassis ground.

   Connector & terminal 

   (B136) No. 1 (+) - Chassis ground (-):

   (B137) No. 7 (+) - Chassis ground (-):

   Is the voltage 13 - 15 V?

   Yes:  Go to  3.

   No:  Repair the open or short to ground in the power supply circuit.

3. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL CONNECTOR. 
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from ECM.
   3. Disconnect the connectors from electronic throttle control.
   4. Measure the resistance of harness between ECM connector and electronic throttle control connector.

   Connector & terminal 

   (B134) No. 19 - (E57) No. 5:

   (B134) No. 29 - (E57) No. 3:

   Is the resistance less than 1 Ω?

   Yes:  Go to  4.

   No:  Repair the harness and connector.

   NOTE: In this case, repair the following item:

   • Open circuit in harness between ECM connector and electronic throttle control connector
   • Poor contact of coupling connector
4. CHECK ECM GROUND HARNESS. 
   1. Connect all connectors.
   2. Turn the ignition switch to ON.
   3. Measure the voltage between ECM connector and chassis ground.

   Connector & terminal 

   (B134) No. 3 (+) - Chassis ground (-):

   (B134) No. 4 (+) - Chassis ground (-):

   (B134) No. 6 (+) - Chassis ground (-):

   (B137) No. 1 (+) - Chassis ground (-):

   (B137) No. 3 (+) - Chassis ground (-):

   Is the voltage less than 1 V?

   Yes:  Check the connector for poor contact and check the harness.

   Replace the ECM if no fault is found. Refer to FUEL INJECTION (FUEL SYSTEMS) (STI)>ENGINE CONTROL MODULE (ECM) .

   No:  Repair the harness and connector.

   NOTE: In this case, repair the following item:

   • Open circuit in ground circuit
   • Further tightening of the engine ground terminal
   • Poor contact of ECM connector
   • Poor contact of coupling connector