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Body Integrated Unit Power Supply And Ground Circuit

NOTE: For the DC power supply circuit, refer to "WIRING DIAGRAMS". Ref. to WIRING SYSTEM > POWER SUPPLY CIRCUIT .

Fig 1: Body Integrated Unit Power Supply And Ground - Wiring Diagram

G10406019

Courtesy of SUBARU OF AMERICA, INC.

CHECK DTC OF BODY INTEGRATED UNIT .
Check DTC of body integrated unit.

Ref. to BODY CONTROL SYSTEM (DIAGNOSTICS) > READ DIAGNOSTIC TROUBLE CODE (DTC) .

Is the DTC of power line displayed on body integrated unit?

Yes: Repair or replace it according to the DTC.

No: Go to 2 .
CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND BATTERY .
1. Turn the ignition switch to ON.
2. Measure the voltage between body integrated unit and chassis ground.
Connector & terminal

(B281) No. 3 (+) - Chassis ground (-):

(B280) No. 32 (+) - Chassis ground (-):

(B281) No. 6 (+) - Chassis ground (-):

(B281) No. 7 (+) - Chassis ground (-):

(i84) No. 6 (+) - Chassis ground (-):

Is the voltage 9 - 16 V?

Yes: Go to 3 .

No: Check harness for open circuit between the body integrated unit and the battery or a blown fuse.
CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND CHASSIS GROUND .
1. Turn the ignition switch to OFF.
2. Measure the harness resistance between the body integrated unit and chassis ground.
  Connector & terminal
  
  (B280) No. 1 - Chassis ground:
Is the resistance less than 1 Ω?

Yes: Go to 4 .

No: Repair the open circuit of harness between the body integrated unit and chassis ground.
CHECK FOR POOR CONTACT .
Is there poor contact of connector?

Yes: Repair the poor contact.

No: Check body integrated unit.