After a year of owning the Tesla Model 3, the car is starting to build the smell of mildew when the AC turns on. The smell goes away after a few minutes, and lucky for my fiancé, she can't smell it, but I can't get over dealing with the smell on a daily basis. The Tesla service center deemed AC smell as something that is not covered under warranty, so it's up to us the car owners to figure this out. Cleaning the AC condenser is technically pretty easy. You just need to find the AC drain pipe, stick the included tube up to the condenser, and just inject the cleaner. Unfortunately, the Model 3's drain pipe is pretty hard to reach as it's smack in the middle of the car and hard to get to without lifting it. Also, the cabin filters are place right behind the condenser, so it's not a good idea to just blast all the cleaning foam from the drain pipe. Lucky for us we can clean from a location we can see the condenser. Tesla released DIY documents on how to replace the air cabin filter, and using that guide, you can remove the cabin filters, and that gives you a clear sight of the condenser. Here is what the condenser looks like The is a ton of empty space on the opposite side of the condenser, so I couldn't just stick the tube in and spray away. There is probably many ways to clean the evaporator. You can probably spray a bunch of mold and mildew cleaner on the condenser and call it a day. Though I already bought a foam cleaner, and so it's time to build something that can let the foam cleaner work its way into the condenser. If you are using a liquid mold and mildew cleaner, look for something that doesn't contain bleach or any chemicals that create harmful fumes. The idea here is to contain the area where the foam would be delivered. I happen to have packing material for a portable hard drive, otherwise I would just cut up a plastic tupperware. The tube is fed to the middle of the cover, and the back is taped with velcro. I then found a piece of wood and taped velcro to the end. The cover happens to be about the same height of the cabin filter. So I just need to move around as I spray the foam cleaner. The whole contraption goes into the cabin filter box like this It was pretty easy to spray the cleaner from this point on. I barely had enough foam to cover the whole condenser. I suggest using the Nextzett Klima cleaner which has much more foam content. After letting he cleaner work itself for 15 minutes, run the fan for a couple of minutes and we're all set to put everything back. Next day the AC smell is gone, and I'm a happy camper. Hope you find this useful! Tesla firmware after Fall of last year will let the fan run for a few minutes after the AC turns off, leaving moisture out and inhibiting mildew growth. Hopefully we don't have to deal with the smell long after this fix.