DTC P0038 Ho2S Heater Control Circuit High (Bank 1 Sensor 2)

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 P0038 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 2) , 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 , PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM:

Fig 1: Wiring Diagram - DTC P0038 HO2S Heater Control Circuit High (Bank 1 Sensor 2)

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE (DTC P0038)

Step		Check	Yes	No
1 CHECK GROUND CIRCUIT FOR ECM. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance of harness between ECM connector and chassis ground. Connector & terminal (B135) No. 4 - Chassis ground: B135 No. 1 - Chassis ground:		Is the resistance less than 5 ?	Go to step 2.	Repair the harness and connector. NOTE: In this case, repair the following: Open circuit in harness between ECM and engine ground cable Poor contact in ECM connector Poor contact in coupling connector
2 CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR. Measure the voltage between ECM and chassis ground. Connector & terminal (B135) No. 2 (+) - Chassis ground (-):		Is the voltage more than 10 V?	Repair the battery short circuit in harness between ECM and rear oxygen sensor.	Repair the poor connection in ECM connector.