So I pretty much have all the electrical gremlins from our car fixed except for one: the AC blower. Currently, it only works on speeds 2 and 3. All the relays have been replaced, as well as circuit breakers, fuses, ect. Fairly sure it is a bad switch but I am wondering if anyone has had similar trouble and maybe has an easy way to 100% diagnose the problem. I don't want to buy a new switch if I'm not certain that is the issue. Thanks!