7-pin plug to 13-pin: This is how you convert!


The temperatures are rising and the holiday or a move is just around the corner, but suddenly you notice: the plug of your bike rack or trailer does not fit in your car. This is mostly because older trailers still have 7-pin connectors and most new cars have 13-pin connectors. To avoid such a scenario, you can convert the trailer’s 7-pin connector to 13-pin. How it works? Read on and find out!


  1. Converting a 7-pin connector to a 13-pin connector: why?
  2. Converting a 7-pin plug to a 13-pin plug: you need this
  3. Switch from 7-pin to 13-pin socket – step-by-step instructions:

Converting a 7-pin connector to a 13-pin connector: why?

To ensure that you are safe on the road with a trailer, it is important that all the lighting works. And this is exactly why you need the trailer plug: so that brake lights, reversing lights and the like are supplied with power and nothing stands in the way of a safe journey with a trailer. To do this, you simply connect the plug of your trailer, bike rack or caravan to the trailer socket of your car. But why would you want to convert a 7-pin connector to a 13-pin? Very easily:

  • Depending on what kind of trailer you are towing with your car, there will be different numbers of poles on the socket.
  • Often there are still 7 poles, although caravans usually already have 13-pole plugs installed.

Tip: Whether you have a 7-pin or a 13-pin connector in front of you – you can quickly tell with the naked eye. A 13-pin connector has – surprise! – 13 poles; a 7-pin connector, on the other hand, has only 7 pins and looks like this:

by the way: If you don’t have a trailer hitch on your car yet, you can easily retrofit one yourself. If the cables are severely or irreparably damaged, you should get a new electrical kit.

7-pin and 13-pin connectors – Here is the difference:

But why are there plugs with different numbers of poles? We explain it to you:

  • There are trailers that only need power to illuminate the brake lights or turn signals.
  • For trailers with reversing lights, you need a 13-pin connector.
  • Caravans also need more electricity – for example for a mini fridge or similar.

In a nutshell: If you convert a 7-pin connector to 13-pin, you will then – logically – have 6 more pins available. and the more poles the plug of your trailer has the more consumers can be supplied with electricity. 13-pin plugs are now standard not only for the popular campers, but also for most modern trailers.

Converting a 7-pin plug to a 13-pin plug: you need this

There are several ways to attach a 7-pin trailer to your car with a 13-pin socket (or vice versa):

  • Changing the 7-pin connector to 13-pin is an option.
  • Another alternative is to use an adapter.


Convert adapter or 7-pin connector to 13-pin?

Using an adapter has a few disadvantages:

  • The adapter is often left plugged in.
  • Water can get into the adapter and thus into the socket.
  • This can cause parts to break.
  • The adapter can be lost.

If you convert (or have converted) the 7-pin connector to a 13-pin connector, you can avoid the latter problems. And of course we’ll tell you how it all works!

Switch from 7-pin to 13-pin socket – step-by-step instructions:

Changing the trailer socket is child’s play. And we’ll show you how to do it with the following step-by-step instructions:

Step 1: Open the 7-pin connector and pull out the cable

This is quite simple:

  • To do this, first unscrew the box (usually 3 screws have to be loosened).
  • Pull out insert, loosen cable
  • Now you can see the 7 cables and the cable lugs that are hidden inside.
  • Carefully pull out the cables.


Tip: The cables have different colors – and these are important for correct assignment. So as long as the colors of the cables are still clearly visible, you don’t have to remember which pole the cable goes to. There is a pin assignment for this, where you can see where the cables go and what is supplied with power. You can see the trailer socket assignment from the following graphic:

trailer socket_occupancy_ATP

No. consumer designation colour
1 left blinker L yellow
2 rear fog light 54g blue
3 Dimensions 31 White
4 right blinker R green
5 light on the right 58R brown
6 brake-lights 54 red
7 light left 58L black
8th reversing light 1 Gray
9 continuous current (continuous pulse) 4 brown/blue
10 charging line 6 brown/red
11 free
12 free
13 Ground for pin 9-12 3 black-and-white

Step 2 Attach cable to 13-pin connector:

  • If the cables withstand the visual inspection and show no signs of damage, the next step is quick:
    • Use the respective colors as a guide to plug the cable into the 13-pin connector at the appropriate point.
  • Otherwise you have to strip the cables for another 4-5 mm so that they can also come into contact with the contacts in the plug and thus conduct the electricity.
    • Please remember: It is best to use wire strippers for stripping.
    • Done? Very good! Then you can also attach the cables to the corresponding sockets using the circuit diagram.
  • Then tighten the screws to prevent the cables from loosening again later.
  • Finally, you simply close the 13-pin plug again – and you’ve already converted your 7-pin socket to a 13-pin one!

Pro Tip: Depending on the intended trailer (e.g. for a caravan) and the actual consumers who rely on continuous electricity, you may need a new electrical kit and/or a connector. Why? Because high consumers have to have a permanent plus in the can. For this you will most likely have to install a corresponding permanent plus-capable cable in your car in advance.


As you can see, converting from a 7-pin to a 13-pin connector is pretty easy in most cases, right?
And how about you? Would you like to convert the 7-pin connector to 13-pin in the near future? Or are you more for the adapter variant? We are very excited about your report!

Source: https://www.atp-autoteile.de/blog/7-poliger-stecker-auf-13-polig-umruesten/

Leave a Reply

Your email address will not be published.