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Home >> Subaru >> 2006 >> Forester XT Limited, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Engine (Diagnostics) (H4DOTC) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

DTC P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

DTC DETECTING CONDITION: 

CAUTION: After repairing or replacing the defective part, carry out the Clear Memory Mode <Ref. to OPERATION , CLEAR MEMORY MODE. > and Inspection Mode <Ref. to PROCEDURE , INSPECTION MODE. >

WIRING DIAGRAM: 

Fig 1: Identifying O2 Sensor Circuit No Activity Detected - Wiring Diagram (Bank 1 Sensor 1)
G05002040Courtesy of SUBARU OF AMERICA, INC.
TROUBLESHOOTING CHART

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 connector 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 

    (B135) No. 8 - (B262) No. 3: 

    (B135) No. 9 - (B262) No. 4: 

Is the resistance less than 1 Ω? Replace the front oxygen (A/F) sensor. <Ref. to FRONT OXYGEN (A/F) SENSOR . > Repair the open circuit of the harness between ECM and front oxygen (A/F) sensor connector.