Restraint > SRSCM > Troubleshooting > B1515 Buckle Switch Driver Defect

General Description

Seat-belt Buckle Switch(BS) is located in driver and passenger side seat. SRSCM checks if seatbelt is buckled by signal of BS. SRSCM controls air bag module and BPT differently in accordance with vehicle speed at the moment of collision and signal from BS.

DTC Description

The SRSCM sets DTC B1515 if there is any fault in BS circuit.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

•	Check current(PWM type)

•	Faulty BS circuit.

•	Faulty BS.

•	Faulty SRSCM.

Enable Conditions

•	Ignition "ON"

Threshold Value

•	7 mA < I < 12mA

Diagnostic
Time

Qualification

•	More tnan 1 sec

De-Qualification

•	More tnan 2 sec

Schematic Diagram

Monitor Scantool Data

1.	Ignition "OFF", connect scantool.

2.	Ignition "ON" & Engine "OFF", select "Diagnostic Trouble Codes(DTC)" mode.

3.	Monitor diagnostic trouble code and present of trouble code.

4.	Using a scantool, clear the DTC.

Is DTC present problem ?

▶ Go to "W/Harness Inspection" procedure.

▶ Displaying nothing(no DTC) or DTC with label "H"(historical) shows that Fault is intermittent caused by poor contact in the part's and/or SRSCM connector or was repaired and SRSCM memory was not cleared.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
▶ Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

Terminal and Connector Inspection

1.	Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2.	Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

	▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
	▶ Go to "Component Inspection" procedure.

Component Inspection

1.	Ignition "ON" & Engine "OFF" and Using a scantool, clear the DTC.

2.	Ignition "OFF".

3.	Disconnect the battery (-) terminal cable from the battery, and wait at least one minutes.

4.	Disconnect Seat-belt Buckle Switch connector.

5.	Substitute the Seat-belt Buckle Switch and check for proper operation.

Is DTC present problem ?

	▶ Substitute a known-good SRSCM, and check for proper operation. If the problem is corrected, replace SRSCM and then go to "Verification of Vehicle Repair" procedure. ▶ Substitute the SRS main harness and check for proper operation. If the problem is corrected, replace SRS main harness and then go to "Verification of Vehicle Repair" procedure.
	▶ Substitute a known-good Seat-belt Buckle Switch, and check for proper operation. If the problem is corrected, replace Seat-belt Buckle Switch and then go to "Verification of Vehicle Repair" procedure.

Verification of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.

1.	Connect scantool and select "Diagnostic Trouble Codes(DTC)" mode.

2.	Using a scantool, clear the DTC.

3.	Operate the vehicle within DTC Enable conditions in General information.

Are any DTC present ?

	▶ Go to the applicable troubleshooting procedure.
	▶ System is performing to specification at this time.