Description
When the ignition switch is on, the center airbag sensor transmits front seat inner belt status signals to the combination meter through the can bus line. If the driver seat belt is not fastened, the combination meter blinks the driver side seat belt warning light. If the seat belt is fastened, the warning light goes off.
Notice:
The seat belt warning system uses the can bus line. Before troubleshooting the seat belt warning system, perform "communication function check" by following "how to proceed with troubleshooting" to confirm that the communication systems are normal.
Wiring diagram

Inspection procedure
Center airbag sensor:

Ok: driver side seat belt warning light operates normally.

Replace center airbag sensor assembly
On-vehicle inspection
Front passenger side seat belt warning light malfunctionDeterioration of battery
Description
The ecm determines the battery power according to the voltage of the batt
terminal while the engine is
running (not cranking).
Inspection procedure
Inspect battery
Inspect the battery specific gravity.
Check the specific gravity of each cell.
Standard gravity: ...
If a warning light turns on or
a warning buzzer sounds
Calmly perform the following actions if any of the warning
lights comes on or flashes. If a light comes on or flashes, but
then goes off, this does not necessarily indicate a malfunction
in the system. However, if this continues to occur, have
the vehicle inspected by your Toyota dealer.
Actions to ...
Catalyst monitor (active air-fuel ratio control type)
Preconditions
The monitor will not run unless:
The mil is off.
Drive pattern
Connect the intelligent tester to the dlc3.
Turn the ignition switch on.
Turn the tester on.
Clear dtcs (if set) (see page es-35).
Start the engine and warm it up.
Drive the vehicle at be ...