I have a 2006 F150 5.4L 4x4 XLT. Last summer the A/C would work for a while and then quit. Then it would work again. Seemed to be related to dry vs. humid days. I also have other electrical issues with the dash. False brake warning light, right speaker cuts in and out. LED display on stereo dims unless you bang on the cover plate, etc.

Ford thought the problem was with the AC clutch or a limit switch, but I was not convinced. Now I am noticing that the heat (which is also controlled by the same analog red/blue ****) is not consistent either. I used to be able to set it to 10:00 position for mild heat. Now I am seeing that it shuts off heat completely (without the cab getting any warmer) and I have to rotate it to about 3:00 in order to get any heat.

I'm thinking the problem is with the HVAC Control Module (which includes the red/blue ****) itself. Any other ideas?