Universal Fitting Tow Bar Wiring

Universal Fitting Tow Bar Wiring

Frequently Asked Questions About Universal Tow Bar Electrics 

Does my vehicle need a bypass relay? 

The easiest way to check this is when searching for tow bars for your vehicle it will often state whether a bypass relay is required or not. The general guidance is that if your car or van has canBUS, multiplexed or very thin wires on the rear lights then a bypass relay should be installed. We have found however, that some vehicles that do not "need" a bypass have had one installed due to the cars indicator relay not being able to cope with the extra power draw of a light board or trailer. 

Do I need a bypass relay when installing a Dedicated Tow Bar Wiring Kit?

No. Dedicated Tow Bar wiring kits come with all the necessary electronics to work with the car or vans existing electrical and data systems.

What is a 7 Way Bypass Relay?


This is an electronic component that is electrically connected between the towing plug wiring and the vehicles rear lighting circuits. The bypass relay connects to the 7 rear lights-: Two Brake lights, two rear side lights, two indicator lights and fog light, required to operate the trailer light board. The relay takes power to run the trailer / light board lights straight from the battery or other suitably powerful non-ignition live feed. The relay only connects to the cars rear light circuits to take the signal to operate from them. This ensures that the vehicles ecu does not see an above normal power draw on any of those feeds when towing. An abnormal draw may cause dash board warnings to activate, such as bulb failure or result in the vehicle shutting down power to that light. The relay therefore, "bypasses" the vehicle hence its name.


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7 Pin ( 12N ) "Single" Tow Bar Electrics Kit With Audible Relay Kit

Product no.: Kit1

£21.75 *
RRP Incl. VAT £39.95
You save £18.20
Product data sheet

7 Pin Universal Tow Bar Wiring with 7 Way Bypass Relay

Product no.: Kit2

£56.40 *
RRP Incl. VAT £67.60
You save £11.20

Tow Trust 7 Pin Single Bypass Electrics + Flange Mounting Plate Kit

Product no.: Kit2SocketPlate5

£60.30 *
RRP Incl. VAT £75.00
You save £14.70
Product data sheet

7 Pin Double (12N & 12S) with Audible and 30amp Self Switching Relay Towing Electrics

Product no.: Kit3andSP6

£69.05 *
RRP Incl. VAT £65.00
Prices incl. VAT