Trying to Regain HVAC Function After 12V Terminal Reverse

As the title says, I carelessly crossed 12v battery terminals during replacement. I've replaced half a dozen fuses, the big 125DC/DC under the front panel. None of the A/C related/labeled fuses were blown in the engine panel or in the cabin panel, yet I've got nothing at the A/C instrument panel (plasmacluster). No lights, no signs of life, which leads me to believe it's not getting power, just not sure what circuit that would be. I've seen mention on a big HVAC fuse in the inverter, but would 12v power interact with that? ECU damage? The only other weird thing going on is there's a cooling fan that now comes on when the car turns on and stays running continuously. Thanks to everyone that contributes to this forum, searching through the mass of knowledge has got me this far, but I'm at a dead end now.