Thread: Electric Trailer Brakes

Until you apply power with the brake controller (or hook up the brake wire to +ve) the brakes should be off.

Maybe it has a break away unit which applies the brakes if it comes away from the vehicle?
Not sure how they work as I've never had one.

Some trailer plugs have 12 volts at the connector used for the electric brakes. If you plug in the trailer and get full brakes you will have to remove that connector only. Otherwise I can't see a problem unless the brakes are actually seized.

The break-away systems I have seen use a steel cable clipped to the towing vehicle. In the event of coupling failure the cable pulls out of a special electrical socket on the trailer, causing a 12V battery on the drawbar to energise the brakes. Some systems have a 12V lantern battery for this job. Trailer laws state how long this battery must hold the brakes on after an incident. I believe it is only mandatory to have break-away brakes on a GTM over 2000kg so it is unlikely your camper will have them. Easy to set up though if you want the extra safety.

I bought a Redarc remote head brake controller for some friends last month, all that sticks out of the dash is a small rotary knob and a LED on a label about 2cm wide and 4cm high. Not a long job to fit either, battery, brake, earth and trailer plug wires and you're done.

Thanks guys - sounds like a issue with the wiring in the trailer - of course what the owner has described could also wheel bearings seizing up as they get hot.

If it is the electric brakes locking up I will just snip the power leads to the brakes.

Cheers

Garry

Same as UteMad said - the electric brakes I've had on campers need a +ve supply to the brakes to actuate them, and if it needed a controller to release the brakes it would be impossible to maneuver when disconnected.

Probably the best way forward is to ask the current owner what brand/model of controller he uses, and also if he knows what brand the brakes are (maybe you can work this out anyway if you know the camper brand/model).

Something I HAVE come across is that different trailer plugs have different wiring, and its possible that the current owner's experience with the locked brakes is relating to hooking up to a car that had an aux feed on what is the brake feed on the camper.

I had a good example if this sort of thing recently. My wife picked up our camper from where it is stored using my recently purchased falcon (without brake controller) since I had the Disco at work.
When she made comment about the brakes coming on in pulses when the indicators were on I twigged that the falcon had a 5pin round plug whereas the camper has a 7pin. They connect together OK, but the the pinout is different, and I'm guessing the indicator wire on a 5pin goes to the brake feed on the 7 pin. Love to meet the moron that decided on the different pinout for 2 physically interchangeable plugs

Steve

Thanks Steve - the problem is the guy does not know much about the trailer he has - as I said never actually used it and did not even know what sort of hitch it has - describing it turns out to be a Tregg. He said that if the car's brake controller is not connected the trailer moves but the brakes slowly come on and lock the wheel, but when the car's brake controller is connected all works as it should. Seems odd to me.

I will take a few extra tools with me when I go to pick it up and pick it up in the morning so I can go to a auto elect if needed.

Cheers

Garry

Sorry Garry - missed that sentence in your first post.

This link has a good video and explanation of the common Alko electric brakes which are the ones I'm familiar with.
AL-KO Website Electric Brakes

Steve

I assume the RRS uses the same wiring as the D3 & D4 whereby the pin that is used for trailer brakes has a 2nd tail-light supply, so when the lights are on, so are the brakes! To make a temporary fix, remove the wire from pin 5 of the trailer plug (its probably blue).

I towed an older pop-top home recently but didn't realize that it has electric brakes, thinking it was too old so didn't look. However there is an electrical fault so they didn't operate when I had the lights on. I haven't fitted my P3 yet so haven't cut the 2nd tail-light supply to the trailer socket.

I have the proper wiring harness connected in the back of car so I also assume I have what you have said (why would they have 2 tail light power supplies). I didn't get the white plug and wiring connected. Is there any point?

Thanks

Garry