For last 6 mos our suburban will just start blowing hot (~116 degrees) air like the heat is on. Then it will fix itself. Sometimes it will work for weeks at a time and other times switches every time you start it. There’s no leak, and I’ve had some success recalibrating the actuator (pulling fuse). It always fails after turning car off. Ie, we’re never driving with cold air and it just starts blowing hot.
The problem is not isolated to just driver, passenger, front or rear. Either the whole system works perfectly or it blows hot out of every vent. Any ideas what I’m dealing with?