Air Bag Systems: Description and Operation
SYSTEM OUTLINE1. SEAT BELT WARNING SYSTEM
WHEN THE IGNITION SW IS TURNED ON, CURRENT FLOWS FROM THE GAUGE FUSE TO TERMINAL 2 OF THE SEAT BELT WARNING RELAY. AT THE SAME TIME, CURRENT FLOWS TO TERMINAL 5 THROUGH THE SEAT BELT WARNING LIGHT. THIS CURRENT ACTIVATES THE SEAT BELT WARNING RELAY AND CURRENT FLOWS FROM TERMINAL 2 RELAY TO TERMINAL 4 TO GROUND, AND THE CURRENT WHICH HAS FLOWED THROUGH THE SEAT BELT WARNING LIGHT FOR APPROX. 4-8 SECONDS FLOWS FROM TERMINAL 5 OF THE RELAY, TERMINAL 6 TO GROUND, CAUSING THE WARNING LIGHT TO LIGHT UP. AT THE SAME TIME AS THE SEAT BELT WARNING LIGHT LIGHTS UP, THE CURRENT APPLIED TO TERMINAL 2 FLOWS THROUGH THE RELAY TO TERMINAL 6 TO BUCKLE SW TO GROUND, CAUSING THE SEAT BELT WARNING BUZZER TO SOUND FOR ABOUT 4-8 SECONDS. HOWEVER, IF THE SEAT BELT IS PUT ON (BUCKLE SW OFF) DURING THIS PERIOD, THEN THE BUZZER WILL STOP.
2. UNLOCK WARNING SYSTEM
WITH THE IGNITION KEY INSERTED IN THE KEY CYLINDER (UNLOCK SW ON), THE IGNITION SW STILL OFF AND DOOR OPEN (DOOR COURTESY SW ON), WHEN A SIGNAL IS INPUT TO TERMINAL 1 OF THE RELAY. THE SEAT BELT WARNING RELAY OPERATES, CURRENT FLOWS FROM TERMINAL 3 OF THE RELAY TERMINAL 4 TO GROUND AND THE UNLOCK WARNING BUZZER SOUNDS.