I got same problem with Crown RC3000. The key seems ok, I tried two other keys both end up with Rekey Error=109.

When turn the key all lights come on but nothing goes on, after left go the key and waited for 10-20 seconds all lights come on but no display on the green led screen. All lights on and the little Maintance icon is on too but can't perform any action at all.

We don't have crown service company here and we need to figure out how to fix it.

Thanks