So as the title states I have a problem with a custom vehicle:

The vehicle is installed in ambulance slot but also was tested on a addon slot.
The problem is whenever I enter the vehicle everything is fine I can turn on and off all lights/emergency lights etc. but when I start driving I get a frozen screen and then the game crashes

Here's a video:
https://streamable.com/kup009
(the render quality was lowered just to export it faster)

Would be amazing if someone could help me!