Unique HVAC Issue?

[jimlem]

I have read dozens of threads on people's HVAC issues and the actuator door problems. I have been looking for days so as not to duplicate something already covered but cannot find anything about my symptoms. I realized all that I saw were dual zone controls; either auto climate control or manual dual controls for driver and passenger. I have an '02 Silverado 1500 HD. I have the plain-Jane manual 3 dial controls. Fan speed, temp, and vent location. I also have 3 buttons; 1 each for fresh, recirc, and A/C. Like others, I recently installed a new battery but my issues did not start until a week later. I have also installed several batteries and never had an issue. The past 3 days, I have had 3 instances where my controls have gone haywire. Twice, while stopped idling in light city traffic, I'll look down and see both the fresh and recirc lights on together and the A/C off. The A/C is always on in my truck. Each of these times the heat was set at just into the warm area, fan was on speed one or two, and vents were set to half way between defrost (full clockwise) and the position before that. It was between the two marked positions. Each time, in addition to the lights above, hot air (hotter than set for) was trickling out of windshield defrost vents, as if no fan running. Both times I had to shut it off and restart to fix it. Last time was all the same settings except vent position was on the second from full CC ie the one splitting air between the dash vents and the floor vents. This time I was driving down the freeway and the same light patterns came up, heat went full hot and from dash vents and this time fans was running faster than set for. I was melting and looking for a spot to stop and desperately flipping dials to try and stop it with no luck. I gave up and set my sights on the upcoming off ramp. Just as I got there, maybe 2 mins max, it fixed itself (or at least gave me control back) and A/C came on, air went to fresh and I was able to dial down temp etc.

 

What I was hoping someone could clarify is: Is there any calibration procedure for my truck? I tried every one I found for the other trucks but nothing happens with mine. There is no whirring of actuators or doors etc. I read somewhere those procedures don't apply to me but I had to try something. Can you tell from the above which or how many actuators or doors are faulting? Does my setup have anything in common with the dozens of dual zone trucks I read about? I don't know where to start because each time it demonstrates issues with the fresh air blend, fan speed problem, heat incorrect and air coming from vents it's not set for. That's like every part failing at the same time. In 10 years, I've never even had a hiccup with the HVAC system and I've gone through 4 batteries. The HVAC has always been one of the best behaved and foolproof parts of the truck. Any help or insights always appreciated.