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DTC P2195: A/F/O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 1: Notes

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>CLEAR MEMORY MODE>OPERATION , and inspection mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>INSPECTION MODE>PROCEDURE ..
Use the check board when measuring the ECM terminal voltage and resistance.

Wiring diagram:

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

G11577046

Courtesy of SUBARU OF AMERICA, INC.

CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR.
Check the front oxygen (A/F) sensor connector.

Has water entered the connector?

Yes: Completely remove any water inside.

No: Go to 2.
CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance between ECM connector and chassis ground.
  Connector & terminal
  
  (E158) No. 15 - Chassis ground:
  
  (E158) No. 27 - Chassis ground:
  
  (E158) No. 39 - Chassis ground:
Is the resistance 1 MΩ or more?

Yes: Go to 3.

No: Repair the short circuit to ground in harness between ECM connector and front oxygen (A/F) sensor connector.
CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.
1. Connect the connector to ECM.
2. Disconnect the connectors from front oxygen (A/F) sensor.
3. Turn the ignition switch to ON.
4. Measure the voltage between ECM connector and chassis ground.
  Connector & terminal
  
  (E158) No. 15 (+) - Chassis ground (-):
  
  (E158) No. 27 (+) - Chassis ground (-):
  
  (E158) No. 39 (+) - Chassis ground (-):
Is the voltage 8 V or more?

Yes: Repair the short circuit to power in the harness between ECM connector and front oxygen (A/F) sensor connector.

No: Repair the poor contact of ECM connector.