I had a heater core leak and changed it. After a good days work of tearing the dash out and all I had it back together and cranked up the Jeep to ensure no leaks, Turned the Heater on after a few and the blower was not working. Took another day of back tracking to make sure I didn't miss anything and still no blower. I have checked the fuses and even changed the Resistor still nothing. What else could it be, I know the fan is good as it was working before, the switch also never gave me a problem so I would assume it is good also.
might locate and replace the blower relay.
I've heard of a lot of issues with the blower switch in your vintage Wranglers, but you can spend a lot of $ throwing parts at it hoping to find the fix. Best bet is to get an electrical multimeter and a manual and start testing. A good manual (maybe Haynes or Chilton) or better yet the Factory Service Manual will outline testing procedures for each component.
