Caravan Breakaway Systems: Where Should You Attach the Cable?

A caravan breakaway system is one of those pieces of towing equipment that most caravanners know they need, but one surprisingly simple question can lead to plenty of debate: where should you actually attach the breakaway cable to your tow vehicle?

The legal requirements around breakaway brakes themselves are relatively clear. However, when you start looking for a specific rule telling you exactly where the cable must be clipped onto the vehicle, things become much less straightforward.

So, what does the law actually say, and what makes sense when you’re hooking up your caravan?

What Does a Caravan Breakaway System Do?

A caravan breakaway system is essentially a last line of defence. If your caravan completely separates from your tow vehicle, a cable connected between the two pulls a pin from the breakaway switch. This activates the caravan’s electric brakes using an independent power supply.

Systems such as the RV Electronics Brake-Safe are designed to activate the trailer brakes if the caravan or trailer accidentally separates from the tow vehicle. These systems have their own power supply and are designed to keep the brakes applied for a period of time after a breakaway.

It is important to distinguish this system from your normal electric brake controller. Your brake controller operates the caravan brakes during normal towing. The breakaway system is there for the much more serious situation where the caravan and tow vehicle separate completely.

When Is a Caravan Breakaway System Required?

In South Australia, a trailer with a Gross Trailer Mass (GTM) exceeding 2,000kg must have a breakaway system that automatically applies the trailer brakes if the trailer becomes disconnected from the tow vehicle.

This reflects the broader Australian requirements. The current ADR 38/05 requires trailers over 2 tonnes GTM to have an emergency braking system that automatically applies the brakes following a disconnection and keeps them applied for at least 15 minutes.

The recently published VSB1 Revision 6 says the same: trailers over 2,000kg GTM require an efficient breakaway braking system, operating on all wheels, with the brakes remaining applied for at least 15 minutes following a separation.

That part is quite clear, but what isn’t nearly as clear is where the breakaway cable attaches to the tow vehicle.

Where Should the Breakaway Cable Be Attached?

After looking through the current ADR, VSB1 and South Australian towing information, we haven’t found a provision prescribing one particular attachment point on the tow vehicle.

The regulations focus primarily on what the system must do rather than specifying exactly where you must clip its cable. In other words, the caravan breakaway system needs to activate automatically if the caravan separates, but the legislation doesn’t appear to say something as specific as “attach the cable to this particular part of the towbar.”

That’s where some common sense, manufacturer guidance, and good engineering practice come into play.

The entire purpose of the cable is to pull the breakaway pin if everything else goes badly wrong. Therefore, you want a solid attachment point that gives the system the best chance of doing exactly that.

As a general principle, avoid attaching it to something obviously weak, temporary or likely to come away during the same failure. That could include:

• a split pin or similarly light-duty component;
• plastic trim, numberplate brackets, or other non-structural components;
• the coupling itself or another component that could disconnect with the caravan.

Whatever you use should also allow the cable to move freely without dragging along the road, becoming pinched or inadvertently pulling the breakaway pin during normal cornering.

Should It Be Attached to the Towbar?

This is where the discussion really becomes interesting.

For many caravanners, the most convenient solid attachment points are around the towbar and safety-chain mounting points. But consider what happens in the unlikely event that the towbar itself separates from the vehicle.

If your breakaway cable is attached to the same assembly that has just fallen away, will it still pull the breakaway pin?

RV Electronics has addressed this exact scenario with its Breakaway Switch Mount. The product can mount around the towbar while also incorporating a separate forward connection to the vehicle. RV Electronics says this arrangement is designed so the breakaway system can still activate in the event of a towbar failure.

That doesn’t mean attaching a breakaway cable to a towbar point is automatically illegal. We haven’t found legislation saying that. Rather, it demonstrates why there can be a difference between meeting a broadly written performance requirement and considering the different ways a towing system could potentially fail.

Where practical, a suitable independent structural attachment point on the vehicle may provide another layer of protection. However, vehicle, towbar, and breakaway-system designs vary considerably, so there isn’t necessarily one attachment solution suitable for every combination.

Coil Cable or Straight Cable?

You’ll commonly see both straight breakaway cables and coiled versions. The principle remains the same.

A coiled cable can make it easier to keep everything neat around the drawbar and prevent excess cable from hanging down. RV Electronics’ Breaksafe coil cable, for example, stretches to 1.2 metres when required and contracts to around 100mm when disconnected.

Whichever style you have, inspect it periodically. Look for fraying, corrosion, damaged clips, damaged insulation or anything else that could prevent it doing its job.

The same goes for the breakaway battery. Check the battery health before a trip to ensure the system will operate properly.

Make the Breakaway System Part of Your Hook-Up Routine

Your caravan breakaway system shouldn’t be an afterthought once the coupling, chains, and electrical connections are sorted.

As part of your normal pre-departure routine, check that the breakaway cable is connected to an appropriate solid point, has enough movement for normal towing and isn’t dragging or likely to snag. Periodically inspect and test the system in accordance with its manufacturer’s instructions, including checking the condition of its battery.

And if you’re uncertain about the correct attachment point on your particular vehicle, don’t guess. Check the instructions supplied by the vehicle, towbar, and breakaway-system manufacturers or speak with a qualified installer.

The legislation is clear about what a caravan breakaway system needs to achieve, but exactly how you create the most reliable attachment between your particular caravan and tow vehicle requires a little more thought.

At Adelaide RV, we want caravanners to understand not just what they need to connect, but why it’s there in the first place. A few extra seconds spent checking your setup before leaving home can help ensure you’re confident, compliant and adventure ready.