DTC P0050 Ho2S Heater Control Circuit (Bank 2 Sensor 1)

WARNING: This page is about a different variant/trim than selected.

DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
GENERAL DESCRIPTION < Ref. to DTC P0050 HO2S HEATER CONTROL CIRCUIT (BANK 2 SENSOR 1) , Diagnostic Trouble Code (DTC) Detecting Criteria. >

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode.> and Inspection Mode < Ref. to , OPERATION , Inspection Mode

WIRING DIAGRAM:

Fig 1: Wiring Diagram - DTC P0050 HO2S Heater Control Circuit (Bank 2 Sensor 1)

Courtesy of SUBARU OF AMERICA, INC.

DTC P0050 DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1. CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Start the engine and warm-up engine. Turn the ignition switch to OFF. Disconnect the connectors from ECM and front oxygen (A/F) sensor. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B134) No. 1 - (E24) No. 6: (B135) No. 7 - (E24) No. 6:	Is the measured value less than 1 Ω?	Go to step 2 .	Repair the open circuit in harness between ECM and front oxygen (A/F) sensor connector.
2. CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector. Connector & terminal (B134) No. 27 - (E24) No. 1: (B134) No. 34 - (E24) No. 3:	Is the resistance less than 1 Ω?	Go to step 3 .	Repair the open circuit in harness between main relay and front oxygen (A/F) sensor connector.
3. CHECK HARNESS BETWEEN OXYGEN SENSOR RELAY AND FRONT OXYGEN (A/F) SENSOR CONNECTOR. Measure the resistance of harness between oxygen sensor relay and front oxygen (A/F) sensor connector. Connector & terminal (B327) No. 4 - (E24) No. 4:	Is the measured value less than 1 Ω?	Go to step 4 .	Repair the open circuit in harness between oxygen sensor relay and front oxygen (A/F) sensor connector.
4. CHECK FRONT OXYGEN (A/F) SENSOR. Measure the resistance between front oxygen (A/F) sensor connector terminals. Terminals No. 6 -No. 4:	Is the measured value less than 5 Ω?	Go to step 5 .	Replace the front oxygen (A/F) sensor. < Ref. to FRONT OXYGEN (A/F) SENSOR . >
5. CHECK POOR CONTACT. Check the poor contact in ECM and front oxygen (A/F) sensor connector.	Is there poor contact in ECM or front oxygen (A/F) sensor connector?	Repair the poor contact in ECM or front oxygen (A/F) sensor connector.	Replace the front oxygen (A/F) sensor. < Ref. to FRONT OXYGEN (A/F) SENSOR . >