interior fans, temp, rear defrost, don’t work all the time. Is there a short or does the whole panel need to be replaced?
That’s why you need an automotive electrician. Things like these need to be diagnosed, and, in this case, can’t be done from a distance. Typically an intermittent electrical issue can be traced to a bad connection. If that connection is in the module, replacing the module is generally the best option. If it is in the wiring, this is harder to find and may be trickier to fix.