Could it be the ingition switch ?

[Mr. Abrasive]

We are still having problums with the Anti-lock brake light, when it comes on the heater/ac wont work. No codes are showing when it happens but its always linked to starting. Sometimes it comes on just after you start the truck, the other day it just came on and air shut off while driving, I touched my key and it ( the light went off and the ac started working. It worked all the way home then not when I started it today. The brakes work, the ac works, the heater works but when the light comes on it cuts off the ac. I dont know what to get fixed if I take it somewhere. A friend suggested the Body Control Module what do these run? anyone know? I'm stumped big time and would appreciate all suggestions. Thanks

[junior3382]

Not sure if you figured this out yet, but I am curious myself.... Could be a problem in the fuse box? maybe just a lose connection? Anyways, did you figure it out?

[Mr. Abrasive]

We were lucky enough to find a good electrical guy who traced it from fuse to switch and found the problum on Friday and had it ready to pick up on Monday. $500.00 later but fixed. Thanks for asking.