Quick answer
You need an adapter when your car’s towing socket and your trailer’s plug are different types. The two common jobs are: a 13-pin car with a 7-pin trailer, or a 7-pin car with a 13-pin caravan. Pick the adapter by what plugs into what. A “13-pin socket to 7-pin plug” adapter lets a modern 13-pin car tow an older 7-pin trailer. For caravans with extra circuits, you may need a twin adapter that splits a 13-pin into both 12N and 12S 7-pins, because a single 7-pin cannot carry the fridge and charging feeds.
| Your car | Your trailer | Adapter you need |
|---|---|---|
| 13-pin socket | 7-pin plug (lights only) | 13-pin to 7-pin (12N) |
| 7-pin socket | 13-pin plug (road lights only) | 7-pin to 13-pin adapter (road lighting only) |
| 7-pin (12N + 12S) | 13-pin caravan | Twin 7-pin to 13-pin |
| 13-pin socket | Twin 7-pin caravan | 13-pin to twin 7-pin |
Adapters are one of those small parts that save a whole day. Your car has one type of socket, the trailer you have borrowed or bought has the other, and rather than rewiring anything you just plug an adapter in between. The only thing people get wrong is buying it the wrong way round, so here is how to be sure.
Work out which way round you need it
Name the adapter by what goes where. Look at your car’s towing socket first, then your trailer’s plug. An adapter described as “13-pin to 7-pin” plugs into a 13-pin car socket and gives you a 7-pin socket for the trailer. If you read it the wrong way you will end up with two plugs and nowhere to connect them, so always check the car end first.
If you are not sure which plug is which, our 7-pin and 13-pin wiring guide shows both connectors side by side.
The caravan catch: lights are not the whole story
For a trailer that only has lights, any straight 13-pin to 7-pin adapter does the job, because the road lighting lives on the same pins. Caravans are different. They also draw a permanent feed and a switched feed for the fridge, charger and interior, and those circuits do not exist on a single 12N 7-pin. That is why caravans historically used two 7-pins, the 12N for lights and the 12S for the living side.
So if you are matching a 13-pin caravan to an older car that has twin 7-pin sockets, you want a twin adapter that splits the 13-pin out to both 12N and 12S. A single 7-pin adapter will give you working lights but no power to the caravan’s habitation electrics.
Quick checklist before you buy
- Check the car socket first, then the trailer plug.
- Lights only? A straight 13-to-7 or 7-to-13 adapter is fine.
- Caravan with a fridge, leisure battery charging and other auxiliary caravan circuits ? Use a twin adapter that carries 12N and 12S.
- Keep the contacts clean and dry, and store the adapter out of the weather.
While you are at it
If you are already sorting connectors, it is a good moment to check the lamps themselves. Swapping tired bulb units for LED gives you brighter, longer-lasting lights that draw less current, which is kinder to older towing electrics. See our rear lights and the full LED trailer lights range, and if your indicators start flashing quickly after fitting LEDs, that is the well-known quirk solved by a 68007 fault eliminator.
You will find adapters and connectors in our accessories range. Not certain which one you need? Send us a quick message with your car and trailer and we will tell you exactly what to order.
