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Home >> Subaru >> 2014 >> Tribeca >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (Diagnostics) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> Diagnostic Procedure
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Diagnostic Procedure

DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK CURRENT DATA. 
  1. Turn the ignition switch to ON.
  2. Read the value of «Atmosphere Pressure» using the Subaru Select Monitor or a Generic scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". Refer to SUBARU SELECT MONITOR . >

  • Generic scan tool

    For detailed operation procedures, refer to the generic scan tool operation manual.

Is the value in «Atmosphere Pressure» 125 kPa (938 mmHg, 36.9 inHg) or more? Go to step . Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.
NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2 CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM and the leak check valve assembly.
  3. Measure the resistance of harness between ECM and the leak check valve assembly connector.

    Connector & terminal 

    (B136) No. 21 - (R400) No. 7: 

    (B135) No. 30 - (R400) No. 8: 

Is the resistance less than 1 Ω? Go to step . Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit in harness between ECM and the leak check valve assembly connector
  • Poor contact of coupling connector
  • Poor contact of joint connector
3 CHECK FOR POOR CONTACT. 
Check for poor contact of ECM and the leak check valve assembly connector.
Is there poor contact in ECM and the leak check valve assembly connector? Repair the poor contact of ECM and the leak check valve assembly connector. Go to step .
4 CHECK LEAK CHECK VALVE ASSEMBLY. 
Check the pressure sensor of the leak check valve assembly. Refer to CHECK PRESSURE SENSOR , INSPECTION, Leak Check Valve Assembly. >
Is the pressure sensor of the leak check valve assembly OK? Repair the short circuit to power in harness between ECM and leak check valve assembly connector. Replace the leak check valve assembly. Refer to LEAK CHECK VALVE ASSEMBLY . >