DTC P0044 Ho2S Heater Control Circuit High (Bank 1 Sensor 3)

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 P0044 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 3) , 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 P0044 HO2S Heater Control Circuit High (Bank 1 Sensor 3)

Courtesy of SUBARU OF AMERICA, INC.

DTC P0044 DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1. CHECK INPUT SIGNAL FOR ECM. Measure the voltage between ECM connector and chassis ground. Connector & terminal (B135) No. 2(+)-Chassis ground (-):	is the measured value more than B V?	Go to step 2 .	Go to step 3 .
2. CHECK CURRENT DATA. Turn the ignition switch to OFF. Repair the battery short circuit in harness between ECM and rear oxygen sensor connector. Turn the ignition switch to ON. Read the data of rear oxygen sensor heater current using Subaru Select Monitor or OBD-II general scan tool. NOTE: Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA FOR ENGINE". < Ref. to , SUBARU SELECT MONITOR . > OBD-II general scan tool For detailed operation procedure, refer to the OBD-II general scan tool instruction manual .	Is the measured value more than 7 A?	Replace the ECM. < Ref. to ENGINE CONTROL MODULE (ECM) . >	END
3. CHECK POOR CONTACT. Check poor contact in ECM connector.	Is there poor contact in ECM	Repair poor contact in ECM connector.	END