Something worth watching out for is if you are using the old 7 pin plug with an adapter into the modern 13 pin type. The car doesn’t always recognise them. I have several things that I tow and also a bike carrier, some on 7 pin with adapter and some on the 13 pin. One of my trailers is fitted with those magnetic pre-wired tail light sets (from the jungle website) and whilst the lights work as they should the car doesn’t recognise they are plugged in and also bongs at me that a tail lamp bulb is out, I assume this to do with how it’s wired, I believe that both tail lamps share the same wire were usually they would be wired separately (i.e the car thinks there is only one tail lamp). Everything else I use works fine. This is a factory fitted tow bar on a Kodiaq. Apologies for the ramble, thought it might be food for thought for you.