DTC P1152 O2 Sensor Circuit Range/Performance (Low) (Bank 1 Sensor 1): Wiring Diagram

Fig 1: Sensor Circuit Range/Performance (Low) (Bank 1 Sensor 1) - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 CHECK FRONT OXYGEN (A/F) SENSOR CONNECTOR AND COUPLING CONNECTOR.	Has water entered the connector?	Completely remove any water inside.	Go to step 2.
2 CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.  Turn the ignition switch to OFF. Disconnect the connectors from the ECM and front oxygen (A/F) sensor. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal  (B135) No. 9 - (E22) No. 1:  (B135) No. 8 - (E22) No. 3:	Is the resistance less than 1 Ω?	Go to step 3.	Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM and front oxygen (A/F) sensor connector Poor contact in front oxygen (A/F) sensor connector Poor contact in ECM connector Poor contact of coupling connector
3 CHECK POOR CONTACT.  Check poor contact of front oxygen (A/F) sensor connector.	Is there poor contact in front oxygen (A/F) sensor connector?	Repair the poor contact of the front oxygen (A/F) sensor connector.	Replace the front oxygen (A/F) sensor. <Ref. to FRONT OXYGEN (A/F) SENSOR . >