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Home >> Subaru >> 2005 >> Outback Limited, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Engine (Diagnostics) (H4SO) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
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DTC P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

DTC DETECTING CONDITION: 

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode.> and Inspection Mode < Ref. to , PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM: 

Fig 1: DTC P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
G03828465Courtesy of SUBARU OF AMERICA, INC.
DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1) DIAGNOSIS

Step Check Yes No
1. CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connectors from ECM and front oxygen (A/F) sensor connector.
  3. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector.

    Connector & terminal 

    (B134) No. 33 - (B395) No. 1: 

    (B134) No. 26 - (B395) No. 3: 

Is the resistance less than 1 Ω? Go to step 2.  Repair harness and connector.
NOTE: In this case, repair the following:
  • Open circuit in harness between ECM and front oxygen (A/F) sensor connector
  • Poor contact in front oxygen (A/F) sensor connector
  • Poor contact in ECM connector
2. CHECK POOR CONTACT. 
Check poor contact in front oxygen (A/F) sensor connector.
Is there poor contact in front oxygen (A/F) sensor connector? Repair poor contact in front oxygen (A/F) sensor connector. Replace the front oxygen (A/F) sensor. < Ref. to FRONT OXYGEN (A/F) SENSOR . >