I would conclude then that the break-away cable shouldn't be attached to the same location as the chains ( the hitch receiver ) or the hitch pin.
One needs to find an attachment point on the frame ( which might be difficult, given few vehicles have frames these days ).
I guess one could have a ring welded to the unibody easily enough.
Problem is the terms used. If it's not to be attached to the ball or ball mount, would it be OK to attach it to the hitch receiver?
If the chains fail, it seems unlikely to be due to a failure of the receiver's chain loops, and that's where I attach the breakaway cable. It seems even less likely that the receiver will come off of the vehicle structure, and I agree that there is a distinct lack of other attachment points in most vehicles, so I have no problem with the idea of attaching the breakaway cable to the receiver. In some cases there is a tow hook or similar on the vehicle which may be suitably located, and in that case it would be suitable for the breakaway cable.
I wouldn't consider welding on to the unibody for this purpose.
I have never heard of properly attached chains failing. I have heard of, and have had myself, trailers breaking away from the hitch. The idea is to stop safely when decoupling occurs, not to stop the trailer if it is going down the road on its own.
To the contrary, I think a major goal of regulations requiring breakaway switches is to handle complete runaway trailers. Chains do fail (I have no idea how often), because they are often not properly attached. At least two other moulded fiberglass travel trailer manufacturers (not Escape, of course) routinely deliver new trailers with clearly defective and inadequate safety chain installations.
I agree that the brakes should come on if the trailer is uncoupled and attached to the tug only by the safety chains, although if the electrical cable is still attached manual activation of the brake controller can be used so the breakaway feature isn't needed.
As Jim mentioned, I can't imagine a senario where the safety chains or the actual trailer hitch that is bolted to the frame of my truck could fail.
I agree that the receiver structure failing is highly unlikely, but in some defective installations the receiver has at least partially come off of the tow vehicle structure.
Chains can certainly fail, due to improper installation, rust, wear from dragging on the ground, etc. None of these things will happen to a diligent trailer operator, but it happens to others.
I think you would be safe attaching the cable to the receiver as it should be welded to the vehicle. Its usually the hitch itself that something goes wrong with that causes separation.
While I agree that the receiver is a suitable attachment point, and problems usually occur in the routinely detached parts of the system (such as the ball mount and the coupler) rather than the receiver-to-vehicle mounting, receivers are
not normally welded to the vehicle, and with modern vehicles they should not be welded.
Do the the trailer brake lights come on when the breakaway cable is pulled?
No. There is no connection between the breakaway switch circuit and the brake lights, and to provide this capability properly would greatly complicate the breakway wiring.
