Toyota 1993 MR2 Wiring Diagrams page 116

SYSTEM OUTLINE
CURRENT ALWAYS FLOWS TO TERMINAL 1 OF THE SEAT BELT WARNING RELAY THROUGH DOME FUSE.
1. 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 OF THE RELAY FROM THE GAUGE FUSE THROUGH THE SEAT BELT
WARNING LIGHT. THIS CURRENT ACTIVATES THE SEAT BELT WARNING RELAY AND, FOR APPROX. 4–8 SECONDS, CURRENT
FLOWING THROUGH THE WARNING LIGHT FLOWS FROM TERMINAL 5 OF THE RELAY
WARNING LIGHT TO LIGHT UP. AT THE SAME TIME AS THE WARNING LIGHT LIGHTS UP, A BUCKLE SW OFF SIGNAL IS INPUT TO
TERMINAL 4 OF THE RELAY, THE CURRENT FLOWING TO TERMINAL 1 OF THE RELAY FLOWS FROM TERMINAL 6
THE SEAT BELT WARNING BUZZER SOUNDS FOR APPROX. 4–8 SECONDS. HOWEVER, IF THE SEAT BELT IS PUT ON (BUCKLE SW
ON) DURING THIS PERIOD (WHILE THE BUZZER IS SOUNDING), SIGNAL INPUT TO TERMINAL 4 OF RELAY STOPS AND THE
CURRENT FLOW FROM TERMINAL 1 OF THE RELAY
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 3 OF THE RELAY, THE SEAT BELT WARNING RELAY OPERATES,
CURRENT FLOWS FROM TERMINAL 1 OF THE RELAY
SERVICE HINTS
UNLOCK WARNING SW [IGNITION SW]
I11
1–5 : CLOSED WITH IGNITION KEY IN CYLINDER
SEAT BELT WARNING RELAY
S 8
6–GROUND : ALWAYS CONTINUITY
3–GROUND : CONTINUITY WITH DRIVER'S DOOR OPEN
7–GROUND : CONTINUITY WITH IGNITION KEY IN CYLINDER
4–GROUND : CONTINUITY WITH DRIVER'S LAP BELT IN USE
5–GROUND : 0 VOLTS FOR 4–8 SECONDS WITH IGNITION SW ON AND APPROX. 12 VOLTS 4–8 SECONDS AFTER IGNITION SW ON
1–GROUND : ALWAYS APPROX. 12 VOLTS
DOOR COURTESY SW
D10
2–GROUND : CLOSED WITH DRIVER'S DOOR OPEN
BUCKLE SW
B 4
1–2: CLOSED WITH DRIVER'S LAP BELT IN USE
TERMINAL 6 GROUND IS CUT, CAUSING THE BUZZER TO STOP.
TERMINAL 6 GROUND, AND THE UNLOCK WARNING BUZZER SOUNDS.
TERMINAL 6 GROUND, CAUSING THE
GROUND AND
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