Thankfully the dealership near me has been good. I had an issue where I noticed that keyless entry wasn't working though the fob had new batteries (and was the

Thankfully the dealership near me has been good. I had an issue where I noticed that keyless entry wasn't working though the fob had new batteries (and was the same with both fobs), nor the "welcome" lighting, and it seemed like the cellular modem was booting up every time. I have a few alterations via OBDeleven, but nothing I thought would mess with that (some lighting stuff, minimize the seat belt chirps, etc.). I forgot to unplug it and when the dealer came up to me and mentioned "Oh, you have ..." I thought the same as you, ah, crap, they're going to blame that, or charge me a diagnostics fee. They just asked what I might have done and asked my permission to wipe anything should the tech think it was necessary. It ended up just being a faulty battery, so the car was shutting down "non-essential" systems to save energy.