Tacoma Extra Cab 4WD L4-2.7L (3RZ-FE) (1999)
Seat Belt Warning Lamp: Testing and Inspection
INSPECT SEAT BELT WARNING LIGHT
a. Remove the integration relay from the No. 1 J/B.
b. Ground terminal 9 on the junction block side connector.
c. Turn the ignition switch ON and check that the warning light lights up.
If the warning light does not light up, inspect the bulb or wire harness.