Coronavirus (COVID-19) Update Fri 24/04/2020: We are now able to dispatch products from following suppliers: Brink, PCT, TowTrust, Witter, Westfalia, ECS & Jaeger. All products from other suppliers cannot be dispatched, therefore they cannot be ordered at this time.
Please read our full COVID-19 statement here.

Wiring Diagrams

An important aspect of towbar fitting is the wiring which is required to power either your trailer lights or caravan internal electrics. This is often overlooked when booking a towbar or can be difficult to understand exactly what your vehicle requires if you have none or very little knowledge.

Basic wiring to the sockets and plugs is a rather straightforward procedure, however when you require audible replays and bypass kits to cope with the complicated cars of today, this is when things can start to get tricky. Luckily for you, we do this day in day out. We are fully conversant with all aspects of towbar wiring and are stockists of ECS, Brink, Westfalia, Witter electric kits who are market leaders in the field of towing and trailer electrics. All towbar electrics we supply have a great reputation for quality and durability.

12 N 7 Pin Wiring Diagram
Colour: Terminal: Purpose:
Left Hand Indicator
Fog Light
Right Hand Indicator
Right Hand Side Tail Light
Brake / Stop Lights
Left Hand Side Tail Light

Single 7 pin electrics, also known as 12N towing electrics are needed to power the lighting on a trailer, caravan, cycle carrier or anything you're towing. (The single 7 pin electrics power left and right indicator and taillights, fog lights and brake lights.)

If you don't require any further power to your towing counterpart, the single 7 pin electrics socket will be your main choice.

12 N 7 Pin Wiring Diagram
12 S 7 Pin Wiring Diagram
Colour: Terminal: Purpose:
Yellow 1 Reversing Light
Blue 2 Battery
White 3 Earth
Green 4 Power Supply
Brown 5 Sensing Device
Red 6 Fridge
Black 7 Earth

Twin electrics is a 2 plug system which combines the single 7 pin 12N electrics socket with a 12S electrics socket. You will need twin electrics if you require more power than what a single 7 pin socket can provide on a pre 2008 manufactured UK caravan (post 2008 UK caravans are fitted with 13 pin connectors). The twin electrics will power everything that a single electrics system powers plus reversing lamp, battery, power supply and fridge. The brown pin 5 in most cases is not used when wiring tow bar electrics and it is important to ensure that the white pin 3 cable is earthed.. In some cases a split charge relay might be needed in order for the power to switch divide from charging a leisure battery and the car battery.

12 S 7 Pin Wiring Diagram
13 Pin Wiring Diagram
Pin: Colour: Function:
1 Yellow Left Hand Indicator
2 Blue Fog Light
3 White Earth
4 Green Right Hand Indicator
5 Brown Right Tail Light
6 Red Brake Lights
7 Black Left Tail Light
8 Pink Reverse
9 Orange Permanent Power
10 Grey Switch Supply
11 White/Black Earth
12 None Not Allocated
13 White/Red Earth

13 pin towing electrics are the most modern style of towing socket, all EU caravans post 2008 will be fitted as standard with a 13 pin electrics connector. This is essentially a 2-in-1 socket, it has all the capabilities as twin electrics in one rather than 2 separate sockets. 13 pin towing are more adaptable for detachable tow bars that have a spring mounted single socket plate that can be folded up behind the bumper so that it's invisible.

Conversion leads are available for 13 pin towing electrics to twin 7 pin towing electrics or twin 7 pin to 13 pin towing electrics if your vehicle has a 13 pin socket and your caravan has twin 7 pin towing plugs or vice versa.

13 Pin Wiring Diagram
Smart 7 Way Bypass Relay
Smart 7 Way Bypass Relay
Smart Self-Switching Relay
Smart Self-Switching Relay