Anti-lock Brake Light 1999 4x4 Suburban

[Mr. Abrasive]

Late in the summer this year as we were driving, the antilock light came on and I pulled over to check things out. We had just taken off in the early AM and maybe it was still warming up? because it went off soon after I stopped. Periodotically it would come on then go off , so would my Ac controls, I started to notice that when I started the car it would stay on and the ac/heater was DOA. It was off and on for a few months and now its always on and the AC/Heater is DOA. Any ideas anyone? Whats the commonality between ABS/ And Climate Controls? I have checked the fuses inside and out and dont see any sign of them being blown.