Which electrics?

Carma Automotive offer 4 different ways of connecting your towbar wiring:

Universal electric hardwire

The universal electric hardwire is the most widely used and affordable way of integrating towing electrics into a vehicle. Almost all vehicles are compatible with this type of fitment.

The universal kit itself includes the socket, which is available in Single (12N), Twin (12S) or Euro (13Pin) (find out more) and an audible buzzer that enables the driver to monitor the condition of the trailer indicator system.

This method of fitment can be used on all types of cars and vans, although some vehicles manufactured after the year 2004 will require a bypass relay to avoid any faults with the car’s bulb monitoring system and CAN (controller area network) computer.

Bypass relays

Bypass relays, combined with standard ‘universal’ towing electrics offer a reliable, robust and cost effective solution for vehicles equipped with CAN bus and complex bulb check systems.

Bypass relays sit between the car’s original wiring and the trailer lights, avoiding any damage or malfunctions to the car’s onboard computer systems. Their main role is to take the electrical load away from the lighting circuit. This results in protecting the vehicle electrics and giving the correct outputs to the trailer board safely and reliably.

Bypass Relay

Smart CAN relays

Smart CAN relays are designed to work on the vehicles original CANBUS system. If your car is CANBUS equipped and the relay is compatible, this device will give you some similar features of what a dedicated wiring kit would offer – but at a fraction of the price.

On some vehicles the Smart CAN relay has the capability of cutting off the fog light(s) and rear parking sensors when towing. It also offers more functionality over a standard bypass relay and can also reduce installation time.

Please note this is not a manufacturer’s approved method of installation. Please check with your local dealer regarding warranty guidelines or leasing terms.

Dedicated wiring kits

Dedicated manufacturer’s approved wiring kits

Dedicated electrical kits are specifically designed for your exact make and model of vehicle.

With vehicle electrics becoming a lot more complex, these manufactured approved wiring kits are tailored to work with your vehicle’s electrical system to give you the maximum features available to aid your towing experience.

The majority of vehicles come equipped with a towbar wiring connection point of some kind. These kits are designed to connect exactly into these original points. Carma Automotive can supply and fit the approved mating connection to ensure the vehicle wiring loom isn’t modified in a way which would cause any warranty issues with your dealer. This type of installation ensures the towing harness is integrated into the vehicle’s electrics as if it was part of the factory build.

Every dedicated wiring kit will differ in terms of what options and features you may get. This all varies on the make and model of your vehicle and what extras were fitted at the factory.

Manufacturer’s wiring kits can also reduce installation time, however they are not all ‘plug ‘n’ play’. Some dedicated systems will need manufacturer’s coding. This tells the vehicle’s onboard computer system that a towbar has now been installed. The coding is essential on certain kits. Without the correct programing you will not get all of the features the kit can offer. Carma Automotive can code/program a wide range of dedicated electric kits.

Key features of dedicated wiring systems (vehicle dependent)

  • Manufacturer specifically designed and approved
  • Complies with manufacturer’s warranty & guidelines
  • Removable without any damage to vehicles wiring loom

Activates various functions on your vehicle (if installed) such as:

  • Hill start assist
  • Suspension adjustment (ASS)
  • Engine electronics & cooling adjustments
  • Trailer Stability Program (TSP)
  • Adaptive Cruise Control (ACC)
  • Brake Electronics
  • Lane Change Assistance
  • Crash anticipation
  • Parking sensor cut out & reversing camera adjustment
  • Rear fog cut out whilst towing (stops reflection from caravan)
  • Advanced bulb dash monitoring system (Alerts you on driver’s dash if bulb failure)

Available in Single (12N) Twin (12S) or Euro (13Pin) (Please contact us to confirm)

Our towbar services include

Towbar Fitting

There are mainly four different designs to consider when choosing your towbar. Each design will vary in terms of appearance, cost and flexibility.

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Carma Automotive offer three different types of sockets for the electrics on your towbar. Choosing what socket you require all depends on what you are towing. 7 Pin, otherwise known as 12N, is the most common and is standard for most UK trailers and caravans.

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Choosing how the towbar electrics are connected to your vehicle is essential for trouble free towing. With car/van wiring becoming more complex, certain vehicles will require additional parts for correct operation off the trailer lights. There are various ways in which this can be achieved.

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Repairs & Upgrades

Keeping you towing safely and providing additional socket upgrades giving you extra convenience when towing are just a few of the towing services we can offer.

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Towbar Coding

In order for all the features of a dedicated kit to be fully functional, some vehicles will require the towing module to be coded or programmed into the vehicle’s onboard computer.

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Get in touch

We strongly believe that communication, honesty, good planning and quality workmanship are key to a first class service.

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