I was told that there is a switch on the back of the dash, not sure where.

On the Amigos you have to take instrument cluster out and move a screw from one hole to another to reset.

Sorry I can't give you better info.

Try using the search feature search for 'O2 sensor'

Steve G

1990 Amigo XS 4x4, BFG MT 35s, Front & Rear ARBs, 5.38s, Tera Lows, custom springs, custom nerf bars, DOR Front Bumper, custom rear bumper, HD 9500 winch, some CalMini & other stuff