Hi!

Any OBD2 compliant vehicle is supported (the vehicle needs to support OBD2, and in the EU/US (and most other places) this is all petrol vehicles from 1996 onwards, and diesels from 2004 onwards).

If the adapter is not able to connect to the vehicle ECU (and the vehicle definitely supports OBD2) then check that the adapter is functioning properly - there's quite a few of the clone adapters (from ebay/amazon) that work on some signalling protocols (that sit underneath the OBD2 protocol), but not all, meaning it will work on some manufacturers, but not others - if you have a bad adapter then the seller should be able to get it replaced with a tested one (as they are aware that some of the clone adapters can be problematic)