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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.

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

G16446233

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR .
1. Turn the ignition switch to OFF.
2. 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 (SHORT TO GROUND) .
1. Disconnect the connector from ECM.
2. Measure the resistance between the ECM connector and engine ground.
  Connector & terminal
  
  (E158) No. 52 - Engine ground:
  
  (E158) No. 51 - Engine ground:
  
  (E158) No. 53 - Engine 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 (SHORT TO POWER SUPPLY) .
1. Connect the connector to ECM.
2. Disconnect the connector from the front oxygen (A/F) sensor.
3. Turn the ignition switch to ON.
4. Measure the voltage between ECM connector and engine ground.
  Connector & terminal
  
  (E158) No. 52 (+) - Engine ground (-):
  
  (E158) No. 51 (+) - Engine ground (-):
  
  (E158) No. 53 (+) - Engine 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.