Plug + Play Adaptor

You must choose the appropriate Elecbrakes Adaptor based on your Tow vehicles’ trailer wiring socket and Trailer plug. The differences are in the shape and pin count.

Start by confirming the socket type fitted to the rear of the tow vehicle, then selecting the trailer plug type.

Elecbrakes provide an adaptor for each combination of commonly available plug and socket, allowing you to connect your vehicle to your new trailer, or vice versa, potentially without changing the plug or socket on your vehicle or trailer. When towing with multiple vehicles, it may be necessary to have more than 1 adaptor type on hand for installation to suit different combinations.

Some combinations will allow cross use, for example:

• Vehicles equipped with a 12 pin flat socket can accept a 12 pin flat or a 7 pin flat adaptor/trailer plug. However, vehicles equipped with a 7 pin flat socket will not accept a 12 pin adaptor/trailer plug.

When using a 7 pin plug/socket, an optional light duty auxiliary may be provided via Pin 2, suitable for up to 15 amp capacity when factoring the combined lighting circuit current draw.

This can be sourced from the tow vehicles battery or ideally, an ignition triggered fuse block. When routing an auxiliary supply to the vehicle socket, please ensure a 20 Amp inline fuse is installed.

For reference, wiring diagrams: https://www.elecbrakes.com/wiring-diagrams/

Vehicles equipped with a 12 pin socket may already have auxiliary power provided to Pin 9 and additional earth via Pin 10.

When advised by your trailer manufacturer of accessories installed that require an auxiliary power/earth supply, or, if the trailer is equipped with a 12 pin plug, it may require auxiliary circuits to be provided via the tow vehicle / socket. The additional auxiliary circuits may be added to the tow vehicle via pins 8-12.

In this scenario, we recommend the use of a 12 pin to 12 pin adaptor to allow throughput of the auxiliary circuits.

Reference to our 12 pin wiring diagrams: https://www.elecbrakes.com/wiring-diagrams/

In some cases, an Anderson plug may be required if the accessories installed have a current draw exceeding 30 amp peak. Please follow the manufacturers recommendations to add the required Anderson plug/circuit.

WARNING – When working with any additional plugs for auxiliary power on the trailer, you MUST ensure that the earth returns for the accessories are separated from the trailer lights and service brake circuits. If your accessories have a shared earth return, it will be possible to overload the earth circuit on one or either of the plugs, should you have a poor earth connection due to corrosion or dirt buildup.

While it is possible to utilise a 7 pin to 12 pin adaptor to enable the lighting circuits/service brake function, any accessories wired via Pins 8-12 on the trailer will not be operational in this scenario.

An optional light duty auxiliary may be provided via Pin 2, suitable for up to 15 amp capacity when factoring the combined lighting circuit current draw.

The design of a 7SR socket includes mounting tabs to support its bulkier fittings, which can lead to a heavier adaptor connection and reduced connection quality during use. For this reason, Elecbrakes does not offer a small round-to-small round adaptor in our current product range. Instead, we recommend either a wired leader installation or replacing the small round plug/socket with a flat-type arrangement.