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Seat Belt Warning System: Inspection

TROUBLE SYMPTOM:

Driver's side seat belt warning light does not turn on or off.

Warning buzzer does not beep.

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 CHECK BODY INTEGRATED UNIT. Connect the Subaru Select Monitor to the data link connector. Turn the ignition switch to ON. (Engine OFF) Turn the Subaru Select Monitor power to ON. Read the data of the driver's seat belt switch using the Subaru Select Monitor. < Ref. to , Subaru Select Monitor. >	Is the seat belt switch display OFF?	Go to step 2 .	Go to step 6 .
2 CHECK SEAT BELT WARNING LIGHT. Read the data of driver's seat belt warning light using the Subaru Select Monitor.	Is the seat belt warning light display ON?	Go to step 3 .	Check the harness between combination meter and body integrated unit.
3 CHECK BODY INTEGRATED UNIT. Connect the driver's seat belt. Read the data of driver's seat belt switch using Subaru Select Monitor.	Is the seat belt switch display ON?	Go to step 4 .	Go to step 6 .
4 CHECK SEAT BELT WARNING LIGHT. Read the data of driver's seat belt warning light using the Subaru Select Monitor.	Is the seat belt warning light display OFF? Also, is the seat belt warning light in the combination meter gone off?	Go to step 5 .	Check the harness between ignition switch and body integrated unit.
5 CHECK SEAT BELT WARNING BUZZER. Connect the driver's seat belt. Turn the ignition switch to ON.	Does the buzzer beep?	Go to step 6 .	Replace the body integrated unit.
6 CHECK DRIVER'S SEAT BELT BUCKLE SWITCH. Insert the tongue plate to the driver's seat belt buckle. Measure the voltage between connector (R8) and chassis ground. Connector & terminal (R8) No. 1 (+) - Chassis ground (-):	Is the voltage more than 10 V?	Go to step 7 .	Repair the harness between driver's seat buckle switch and chassis ground.
7 CHECK DRIVER'S SEAT BELT BUCKLE SWITCH. Disconnect connector (R8) from driver's seat inner belt. Measure the resistance between connector (R8) terminals and chassis ground. Connector & terminal (R8) No. 1 - Chassis ground: (R8) No. 3 - Chassis ground:	Is the resistance more than 1 MΩ?	Go to step 8 .	Replace the driver's seat inner belt. < Ref. to FRONT SEAT BELT . >
8 CHECK BODY HARNESS. Measure the voltage between connector (R167) and chassis ground. Connector & terminal (R167) No. 11 (+) - Chassis ground (-):	Is the voltage more than 10 V? Also, does the seat belt warning light come on?	Go to step 9 .	Repair or replace the driver's seat inner belt and body harness.
9 CHECK BODY INTEGRATED UNIT. Measure the voltage between connector (i84) and chassis ground. Connector & terminal (184) No. 4 (+) - Chassis ground (-):	Is the voltage more than 10 V?	Go to step 10 .	Check the body integrated unit.
10 CHECK COMBINATION METER. Measure the voltage between connector (R167) and chassis ground. Connector & terminal (R167) No. 20 (+) - Chassis ground (-):	Is the voltage more than 10 V? Also, does the seat belt warning light come on?	Go to step 11 .	Replace the body integrated unit.
11 CHECK COMBINATION METER. Measure the voltage between connector (i10) and chassis ground. Connector & terminal (i10) No. 9 (+) - Chassis ground (-):	Is the voltage more than 10 V? Also, does the seat belt warning light come on?	Go to step 12 .	Check the combination meter.
12 CHECK SEAT BELT WARNING SYSTEM. Disconnect the driver's seat belt. Turn the ignition switch to ON.	Does the seat belt warning buzzer beep and warning light blink for 6 seconds after turning the ignition switch to ON?	Go to step 13 .	Replace the body integrated unit.
13 CHECK SEAT BELT WARNING SYSTEM. Wait for 6 seconds from the step 12 condition (seat belt warning buzzer beeps and warning light blinks).	Does the seat belt warning light repeat illuminating/blinking every 15 seconds, and the warning buzzer beep?	Go to step 14 .	Replace the body integrated unit.
14 CHECK SEAT BELT WARNING SYSTEM. Connect the driver's seat belt buckle in the step 13 condition (seat belt warning light repeat illuminating/blinking every 15 seconds, and warning buzzer beeps).	Does the seat belt warning light go off and the buzzer stop?	Go to step 15 .	Replace the body integrated unit.
15 CHECK SEAT BELT WARNING SYSTEM. Disconnect the driver's seat belt.	Does the seat belt warning light repeat illuminating/blinking every 15 seconds?	Go to step 16 .	Replace the body integrated unit.
16 CHECK SEAT BELT WARNING SYSTEM. Lift-up the vehicle. NOTE: Raise all wheels off the floor. Start the engine, and set the vehicle speed to more than 15 km/h (9 MPH). NOTE: When there is a speed difference between front and rear wheels, the ABS or VDC warning may light, but this does not indicate a malfunction. When diagnosis is complete, perform clear memory for ABS or VDC. < Ref. to OPERATION . > or < Ref. to SUBARU SELECT MONITOR . >	Does the seat belt warning light repeat illuminating/blinking every 15 seconds?	Go to step 17 .	Replace the body integrated unit.
17 CHECK SEAT BELT WARNING SYSTEM. Connect the driver's seat belt in the step 16 condition.	Does the seat belt warning light go off and the buzzer stop?	Go to step 18 .	Replace the body integrated unit.
18 SEAT BELT WARNING SYSTEM. Disconnect the driver's seat belt in the step 17 condition.	Does the seat belt warning light repeat illuminating/blinking every 15 seconds?	Go to step 19 .	Replace the body integrated unit.
19 CHECK SEAT BELT WARNING SYSTEM. Connect the driver's seat belt.	Does the seat belt warning light go off and the buzzer stop?	Temporary poor contact.	Replace the body integrated unit.