DTC P2196: A/F/O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 1: Notes

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DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Wiring diagram:

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

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 (OPEN) .
1. Disconnect the connector from ECM.
2. Disconnect the connector from the front oxygen (A/F) sensor.
3. Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.
  Connector & terminal
  
  (E158) No. 43 - (E24) No. 1:
  
  (E158) No. 56 - (E24) No. 4:
  
  (E158) No. 44 - (E24) No. 5:
Is the resistance less than 1 Ω?

Yes : Go to 3.

No : Repair the following item.
- Open circuit in harness between ECM connector and front oxygen (A/F) sensor connector
- Poor contact of coupling connector
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) (H4DOTC)>FRONT OXYGEN (A/F) SENSOR .