2007 Chevy Avalanche LTZ
 

My AC coil is freezing solid, I know this because when it stops blowing air I turn off the * (COLD AC) and in a few seconds it pumps air, then I turn it back on and a few min later same problem... only happens in low fan and highway driving...

I was told it was the AC Temp Sensor... pic attached but I cant find anything o
https://cimg1.ibsrv.net/gimg/chevrol...4d2a7c4414.jpg
nline about it.

could be low on freon

Nope, checked it.

high humidity will cause this. Happens every time I'm at my beach house but happens no other time.

How did you check refrigerant? Unless you recover all the refrigerant and weigh it back in, you have no idea if the fill is low or high. You can only guess by the actual pressure and ambient temperature.

Removed it and refilled with new at a buddy's shop...
I live in Miami we got humidity year round... this just started happening after the vent actuator stopped working so I replaced them.