Have a trailer here with an on board brake controller.

Issue is the plug was rewired (not by me) and while it looks OK, when you apply the brakes in the towing vehicle, the trailer wheels brake momentarily, then the brake fuse in your vehicle blows.

How are electric brakes supposed to be wired up?

The controller installed is the same as this one

https://www.ebay.com.au/itm/Brake-Co...-/323078407323


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