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· Registered
66 Posts
Discussion Starter · #1 ·
When I ordered my wing in August, I also ordered a hitch, trailer wiring harness, and an isolation harness. To make a long story short, I have no faith in that dealer anymore and am through with them.
The hitch is installed and the wiring is hanging down there with the hitch. I am wondering how to tell if an isolation kit was installed as well. Can I follow the wiring back up somewhere and see the isolator? How will it be identified to differentiate from just trailer wiring?
I am building an HF trailer and know I need to order a 5-4 converter, so I would like to order all at one time if I need to order an isolator as well. If there is an isolation kit in there and I miss it, will it hurt anything if I have a second one?
After installing my spoiler with directions laid out by rmcapozzi, I have some confidence going now. More confidence in this board than in myself so I humbly wait on advice.
If you have not seen rmcapozzi's thread on installing a spoiler, let me recommend it highly. That is the way to lay out instructions!

Thanks again Rob, and thanks in advance for all the help here!

· Premium Member
5,981 Posts
Are the output fuses the difference between the isolation harness and just trailer wiring harnesses?
Thanks for the help Jeff
Actually relays are what makes the harness "isolation." The harness gains power from a direct link to the batter and then passes that power through the relays to the lights. The relays are "tripped" by the current from the bike lights. But, there is no additional load of the trailer lights placed on the wiring for the bike's lights. Yes, there are also fuses in most harnesses downstream from the relays for normal protection in case of a short. Hope this helps.

There is some more information on EC web site at:

· Registered
750 Posts

If the isolator is behind the license plate, and if you have a quite area to do this test, it should be easy:

Key on engine off.
Have somebody hit the brakes and you should be listening right at the license plate area. If the relay is installed, you can hear the relay energize and de energize as you hit the brakes and release. hit and release. hit and release.

If you have the brakes, you likely have the rest since it is one system.

The flasher and tails are harder to hear because of other noises.
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