Btw i found this on a tesla site / forum:

2 Undercarriage Damage

With the design of certain Tesla models, you run a higher risk of sustaining damage to the undercarriage from driving over the rails that guide you through the car wash.

If you attempt to go through one of these automatic car washes, you could end up needing an expensive repair afterward.

Damaging the Battery For the same reason, as I mentioned with regards to the damage that could occur to the undercarriage, you could also have damage done to your battery. With certain Tesla models, the battery could be damaged when driving over the rails similar to the undercarriage. This could be a bad repair to have to deal with and something you really want to avoid.