Body Integrated Unit Power Supply And Ground Circuit

WARNING: This page is about a different car, the 2008 Subaru Impreza. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Body Integrated Unit Power Supply And Ground Circuit Diagram

Courtesy of SUBARU OF AMERICA, INC.

BODY INTEGRATED UNIT POWER SUPPLY AND GROUND REFERENCE

Step	Check	Yes	No
1 CHECK DTC OF BODY INTEGRATED UNIT. Check DTC of body integrated unit. <Ref. to OPERATION , Subaru Select Monitor . >	Is the DTC of power line displayed on body integrated unit?	Repair or replace it according to the DTC.	Go to step 2.
2 CHECK HARNESS CONNECTOR BETWEEN BODY INTEGRATED UNIT AND CHASSIS GROUND. Turn the ignition switch to ON. Measure the voltage between body integrated unit and chassis ground. Connector & terminal (B280) No. 1 (+) - Chassis ground (-): (B280) No. 6 (+) - Chassis ground (-): (B280) No. 7 (+) - Chassis ground (-): (B281) No. 2 (+) - Chassis ground (-):	Is the voltage 9 - 16 V?	Go to step 3.	Check harness for open circuit between the body integrated unit and the battery or a blown fuse.
3 CHECK HARNESS CONNECTOR BETWEEN BODY INTEGRATED UNIT AND CHASSIS GROUND. Turn the ignition switch to OFF. Measure the harness resistance between the body integrated unit and chassis ground. Connector & terminal (i84) No. 28 - Chassis ground: (B279) No. 27 - Chassis ground: (B280) No. 17 - Chassis ground: (B281) No. 20 - Chassis ground:	is the resistance less than 1 Ω?	Go to step 4.	Repair the open circuit of harness between the body integrated unit and chassis ground.
4 CHECK POOR CONTACT.	Is there poor contact in connector?	Repair the poor contact.	Check the body integrated unit.