2004 grand prix

Hmm....well, normally all of that stuff would be protected from the water jets in a car wash...however... I'm not sure if that car has a Cabin Air Filter or not. If it does, there's a possibility that water blasting around the cowling area may have gotten it wet, impeding its ability to flow any air. That's an *if* though, it may or may not have one. Pop the hood and with the key in the On position but the engine Off,...If you turn the blower fan on, can you hear the blower motor kick on at all? You should be able to, from either inside the car or under the hood...

Check the fuses in case one has blown for some reason. Then let the car dry out good for a day or two. If a bit of moisture got into a relay or switch or electrical connection, it will evaporate and start working again. After that you might need someone with automotive electrical expertise to have a look at it.