can i tow a trailer with electric brakes without a brake controller

Short answer: no—you shouldn’t tow a trailer with electric brakes without a proper brake controller.

In Australia, trailers up to 750 kg don’t need brakes; from 751–2000 kg they need brakes, and if those brakes are electric, they must be controllable from the driver’s seat via a controller (built-in, dash-mounted, or even a wireless unit). Above 2000 kg you’ll also need a breakaway system and a controller is non‑negotiable. Towing with the electric brakes inactive is unsafe, illegal in most jurisdictions, and a gift-wrapped excuse for insurers to walk away after a prang. Fit a controller that matches your trailer’s setup (electric or electric‑over‑hydraulic), then test and adjust gain on a quiet road. Check VSB1/ADR rules and your state regs to keep it all above board.