I wanted to post this warning because it has the potential to be a problem for any trailer with brake wires routed through the axle tubes.
My Landmark had the brake wires routed through the axle tubes from the power source on the left side to the brakes on the right. The wires were similar to 18 gauge lamp cord with standard insulation. The wires passed through a grommet at each end of the axle tube and then laid freely within the axle tube. It makes a neat looking package with the wires out of view.
The problem is with the wires inside the axle freely moving as the axle vibrates during travel. Since the wires are not perfectly flat and have some bends in them, the insulation will wear slowly at the points where a bend makes contact with the axle tube. Eventually the insulation will be worn through and the bare wire will make contact with the axle tube. That will cause a short, blow a fuse and cause the brakes to fail.
At first, when the wire makes its first contact it is a very tiny area and may cause a momentary failure or warning and then as the wire moves a bit the brakes will go back to a normal mode. It will get worse as more of the insulation wears away.
My brake controller gave me a warning message that there was a problem. I checked all the external wiring and it looked fine. Since I had this same problem on a previous TT, I pulled the wires out of the axle tubes and found one of the wires to be worn through and the other beginning to do the same. In addition, the wire that was worn was lying in water inside the axle.
I have attached two photos of the wire so readers can get the idea of what I am saying. Sorry I couldn't focus the camera any better at the close range.
I replaced the wire with heavily insulated 18 gauge wire and attached it to the outside of the axle tubes with nylon straps.
One other idea that I like is to have a 30 Amp. self-resetting circuit breaker in the brake line rather than a fuse in the event of a short of this nature.
My Landmark had the brake wires routed through the axle tubes from the power source on the left side to the brakes on the right. The wires were similar to 18 gauge lamp cord with standard insulation. The wires passed through a grommet at each end of the axle tube and then laid freely within the axle tube. It makes a neat looking package with the wires out of view.
The problem is with the wires inside the axle freely moving as the axle vibrates during travel. Since the wires are not perfectly flat and have some bends in them, the insulation will wear slowly at the points where a bend makes contact with the axle tube. Eventually the insulation will be worn through and the bare wire will make contact with the axle tube. That will cause a short, blow a fuse and cause the brakes to fail.
At first, when the wire makes its first contact it is a very tiny area and may cause a momentary failure or warning and then as the wire moves a bit the brakes will go back to a normal mode. It will get worse as more of the insulation wears away.
My brake controller gave me a warning message that there was a problem. I checked all the external wiring and it looked fine. Since I had this same problem on a previous TT, I pulled the wires out of the axle tubes and found one of the wires to be worn through and the other beginning to do the same. In addition, the wire that was worn was lying in water inside the axle.
I have attached two photos of the wire so readers can get the idea of what I am saying. Sorry I couldn't focus the camera any better at the close range.
I replaced the wire with heavily insulated 18 gauge wire and attached it to the outside of the axle tubes with nylon straps.
One other idea that I like is to have a 30 Amp. self-resetting circuit breaker in the brake line rather than a fuse in the event of a short of this nature.
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