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Home >> Subaru >> 2006 >> Outback i, Automatic >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 22 (Engine Controls - Engine (Diagnostics) (H6DO)) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0139 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
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DTC P0139 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)

WARNING: This page is about a different variant/trim than selected.

DTC DETECTING CONDITION: 

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

WIRING DIAGRAM: 

Fig 1: Rear Oxygen Sensor - Wiring Diagram
G05019030
DTC P0139 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2) - DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK FOR ANY OTHER DTC ON DISPLAY.  Is any other DTC displayed? Check DTC using "List of Diagnostic Trouble Code (DTC)". < Ref. to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . >
NOTE: In this case, it is not necessary to inspect DTC P0139.
Go to step 2. 
2 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM and rear oxygen sensor.
  3. Measure the resistance of harness between ECM and rear oxygen sensor connector.

    Connector & terminal 

    (B135) No. 4 - (E61) No. 3: 

Is the resistance less than 1 Ω? Go to step 3.  Repair the open circuit of harness between ECM and rear oxygen sensor connector.
3 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR. 
Measure the resistance between rear oxygen sensor harness connector and chassis ground.
Connector & terminal 
(E61) No. 3 - Chassis ground 
Is the resistance more than 1 MΩ? Go to step 4.  Repair the chassis short circuit of harness.
4 CHECK REAR OXYGEN SENSOR. 
Measure the resistance between rear oxygen sensor terminals.
Terminals No. 3 - No. 4: 
Is the resistance less than 1 Ω? Replace the rear oxygen sensor. < Ref. to REAR OXYGEN SENSOR . > Temporary poor contact occurs. Check poor contact of connector.