DTC P2196: A/F/O2 Sensor Signal Biased/Stuck Rich 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>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR AND COUPLING CONNECTOR  .

   Check the front oxygen (A/F) sensor connector and coupling connector.

   Has water entered the connector?

   Yes: Completely remove any water inside.

   No: Go to  2 .

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. Disconnect the connectors from front oxygen (A/F) sensor.
   4. Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.

   Connector & terminal 

   (E158) No. 46 - (E47) No. 3:

   (E158) No. 33 - (E47) No. 4:

   Is the resistance less than 1 Ω?

   Yes: Go to  3 .

   No: Repair the harness and connector.

   NOTE: In this case, repair the following item:

   • Open circuit in harness between ECM connector and front oxygen (A/F) sensor connector
   • Poor contact of coupling connector
3. CHECK FOR POOR CONTACT  .

   Check for poor contact of the front oxygen (A/F) sensor connector.

   Is there poor contact of front oxygen (A/F) sensor connector?

   Yes: Repair the poor contact of front oxygen (A/F) sensor connector.

   No: Replace the front oxygen (A/F) sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H6DO)>FRONT OXYGEN (A/F) SENSOR .