Can-Bus, ELM, Auto Scanners, AutoTap Don't be a swapper of parts, if you have an OBD-II reader you can plug into to the diagnostics port on your car, be it a Volkswagon, Mercedes, Audi, Ford or any American Market vehicle. You could discover what the issue is before you begin your car repair. There's no need to swap auto parts and hope that you fix the complication when you can have the supplies and tools you require.