Seat Belt Warning System: Inspection

CAUTION:

Before handling the airbag system components, refer to "CAUTION" of "General Description" in "AIRBAG SYSTEM". Ref. to AIRBAG SYSTEM>GENERAL DESCRIPTION>CAUTION .
When inspecting the airbag main harness, disconnect the connectors of the driver's airbag module, passenger's airbag module and knee airbag module for safety reasons.
When inspecting the airbag rear harness, disconnect the side airbag module connector, curtain airbag module connector and seat belt pretensioner connector for safety reasons.

Trouble symptom:

Driver's and passenger's seat belt warning lights do not illuminate or they remain illuminating.
Warning buzzer does not beep.

CHECK FUNCTION.
1. Sit on the driver's seat and passenger's seat and disconnect the seat belts of the both.
2. Turn the ignition switch to ON (engine OFF).
3. Check if the driver's seat belt warning light in the combination meter and the passenger's seat belt warning light in the hazard switch assembly, and if the buzzer sounds.
Do the driver's warning light and passenger's warning light blink and the buzzer sound while blinking?

Yes : Go to 2.

No : Go to 8.
CHECK FUNCTION.
1. Wait until the buzzer sound stops in step 1. (For approximately six seconds after starting sounding)
2. Connect and disconnect the seat belts of the driver's and passenger's.
3. Check if the driver's seat belt warning light in the combination meter and the passenger's seat belt warning light in the hazard switch assembly.
Do the seat belts warning light illuminate ↔ go off according to the operation?

Yes : Go to 3.

No : Go to 4.
CHECK FUNCTION.
1. Wait until the buzzer sound stops in step 2. (For approximately six seconds after starting sounding)
2. Start the engine, and set the vehicle speed at 20 km/h (12 MPH) or more.
3. Check the seat belt warning lights of the driver's and the passenger's, and if the warning buzzer sounds.
Do the driver's warning light and passenger's warning light blink and the buzzer sound while blinking?

Yes : Go to 4.

No : Go to 9.
CHECK HARNESS.
1. Disconnect the negative terminal from the battery, and wait for 60 seconds or more.
2. Disconnect the connectors of the combination meter and the driver's seat belt buckle switch.
3. Check for short circuit to battery, open circuit and short circuit to ground between the combination meter and the driver's seat belt buckle switch.
  Connector and terminal.
  
  (i10) No. 4 - (R108) No. 1:
Is the harness OK?

Yes : Go to 5.

No : Repair or replace the harness.
CHECK HARNESS.
Measure the resistance between the driver's seat belt buckle switch and chassis ground.

Connector and terminal.

(R108) No. 2 - Chassis ground:

Is the resistance less than 10 Ω?

Yes : Go to 6.

No : Repair or replace the harness.
CHECK DRIVER'S SEAT BELT BUCKLE SWITCH.
Measure the resistance between the connector terminals of the driver's seat belt switch when the driver's seat belt is fastened and detached.

Connector and terminal.

(R108) No. 1 - (R108) No. 2:

Is the resistance when the belt is fastened 1 MΩ or more, and less than 10 Ω when the belt is detached?

Yes : Go to 7.

No : Replace the belt assembly front INN LH. Ref. to SEAT BELT SYSTEM>FRONT SEAT BELT>REMOVAL>BELT ASSEMBLY FRONT OUT .
CHECK DATA MONITOR.
1. Sit in the passenger's seat.
2. Using Subaru Select Monitor, select [Data monitor] and display the data of [Belt Buckle Switch RH].
  NOTE: For detailed operation procedures, refer to "Help" of application.
3. Fasten and detach the passenger's side seat belt buckle, and read the data of the seat belt switch. Ref. to DATA MONITOR .
Does the seat belt switch display [Belted] ↔ [Unbelted] according to the operation of the seat belt buckle?

Yes : Go to 9.

No : Go to 8.
CHECK AIRBAG SYSTEM AND OCCUPANT DETECTION SYSTEM.
Perform the check in accordance with the diagnostic procedure DTC B1650 of the airbag system. Ref. to OCCUPANT DETECTION (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE DTC B1650 OCCUPANT DETECTION SYSTEM MALFUNCTION .

Is the inspection result OK?

Yes : Go to 9.

No : Repair or replace with new parts according to DTC B1650.
CHECK PASSENGER'S SEAT BUCKLE SWITCH.
Perform the check in accordance with the diagnostic procedure DTC B1655 of the airbag system. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE DTC B1655 FRONT BUCKLE SWITCH RH FAILURE .

Is the inspection result OK?

Yes : Go to 10.

No : Repair or replace with new parts according to DTC B1655.
CHECK AIRBAG CONTROL MODULE AND COMBINATION METER.
Perform the inspection according to the basic diagnostic procedure for LAN system. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

Is the inspection result OK?

Yes : Go to 11.

No : Repair or replace with new parts according to the diagnostic procedure.
CHECK HAZARD SWITCH ASSEMBLY POWER SUPPLY VOLTAGE.
1. Disconnect the hazard switch assembly connector.
2. Turn the ignition switch to ON.
3. Measure the voltage between the ignition power supply and the hazard switch assembly.
  Connector and terminal.
  
  (i333) No. 10 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes : Go to 12.

No : Check the harness for open or short between the fuse and hazard switch assembly.
CHECK GROUND CIRCUIT OF HAZARD SWITCH ASSEMBLY.
1. Turn the ignition switch to OFF.
2. Measure the resistance between the hazard switch assembly and chassis ground.
  Connector and terminal.
  
  (i333) No. 16 - Chassis ground:
Is the resistance less than 10 Ω?

Yes : Go to 13.

No : Repair or replace the harness.
CHECK HARNESS BETWEEN HAZARD SWITCH ASSEMBLY AND COMBINATION METER.
1. Disconnect the harness of the hazard switch assembly and combination meter.
2. Measure the resistance between the hazard switch assembly and combination meter.
  Connector and terminal.
  
  (i333) No. 14 - (i10) No. 12:
Is the resistance less than 10 Ω?

Yes : Go to 14.

No : Repair or replace the harness.
CHECK COMMUNICATION STATUS BETWEEN HAZARD SWITCH ASSEMBLY AND COMBINATION METER.
1. Remove the hazard switch assembly, and install a properly operating hazard switch assembly (new hazard switch assembly).
2. Connect the connector and then turn the ignition switch to ON.
  Connector and terminal.
  
  (i333) No. 14 - (i10) No. 12:
Is the hazard switch assembly properly displayed?

Yes : Replace the hazard switch assembly.

No : Replace the combination meter case assembly.