2005 F-150 battery question

[Dr. Evil]

All of a sudden, my truck will not switch between air location modes when running the AC. It’s stuck blowing air on my feet. Someone told me this is the first thing that stops working when your battery is getting bad. Anyone ever experience this phenomenon?

Thanks

[Walker]

Thats a blend door problem and I think it works off vacumn. Maybe somethind fell down your defrost vents.

[Kingfisher789]

Doc I think your thinking of GM products that relearn HVAC stepper motor position after a battery replacement.

[super_dave]

2005 F-150 battery question

Yes I’ve had a/c issues right before a battery went bad, it’s weird.

I’ve also had blend door issues without battery failure

[DSMCasey]

My f-150 had this issue and it was a vacuum issue.
A vac hose got brittle and broke. Mine is an 01 though so not sure if they switched to elecronic blending mechanism by 05.

[Dr. Evil]

For you non-believers, I put in a new battery and air blender works like a champ. Old battery tested and found to be very weak. Had someone tell me that when the battery gets weak, the truck will start turning off non-essential things, such as air blender.