For a long time, the 7 pin socket has been the mainstay of towing connections, but in it’s long history, it has been dogged by various problems. This has been most prevalent with the 12S socket with issues such as  'pin burn-out' and bad pin contact and so on.

Likewise the 12N socket has not been without it’s problems with compressed pins, badly fitting plugs, water damage etc.

With the advances in vehicle electronics and greater import and export of caravans to the continent, the 13 pin has become vital for use within the towing market. As a result, several committees were formed here in the UK to examine how best to make the change to 13 pin. 
 

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All towing sockets fall within an ISO (International Standads Organisation) design and the UK representative committees of ISO, the BSI (British Standards Institute) met together and agreed to adopt the 13 pin as a natural replacement for 12N/12S. Following on from this, The NCC ( National Caravan Council ), Caravan manufacturers and various other interested parties met together and likewise decided to adopt the 13 pin system. The inception date for caravans produced with the 13 pin plug is to be - September 2008.

The 13 pin system is likely to be that as described in ISO 11446.

This design is the most widespread throughout Europe and following a survey conducted by the Caravan Club, many members who had this system fitted, have been more than happy with the connection.

Our concern at Right Connections has been from a vehicle electronics aspect. With the increase in advanced vehicle electronics, connections are vital for electronic trailer stability. Therefore, in our opinion, the ISO 13 pin is the safest form of connection currently available between the towing vehicle and towed vehicle.

13 pin to 7 pin

With the changes taking place, there will always be the need for  'adaptor kits' to cope with the different connections between the car and caravan.

The situations likely to arise are:

• 2 x 7 pin sockets on the car to 13 pin plug on the trailer/caravan.

• 13 pin socket on the car to 2x 7 pin plugs on the trailer/caravan.

Right Connections has purpose made, fully tested, 'adaptors' to handle these variations.

Advantages:

• Watertight fitting

• Twist-lock coupling system removing the need to use force.

• Single socket mounting - good for detachable towbar systems

• Single plug on the caravan/trailer

Disadvantages:

• Need for adaptors

We have provided a guide to pin functions and wire colours which you may find useful especially when viewing
website forums and owners club websites.

The wire colours and wire sizes are recommendations made in the relevant ISO No. shown below each chart:

ISO 11446 - 13 pin socket functions

ISO 11446 & ISO 4143-3  - recommended wire size and colours

Further information can be found by clicking on any of the links below:

International Organization for Standardization

More links to follow...