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Immobilizer antenna short circuit error after light install

dbx

Just got it firing!
Joined
Apr 4, 2019
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Location
Duluth, MN
I recently installed on my v85tt some driving lights with a lighting controller to tie in to the high beams. The installation seemed to go well, and everything works correctly. But after finishing the installation, the bike shows a dash error b0005: immobilizer antenna short circuit to positive. I'm not sure what caused it but I'd love to figure it out.

The thing is, I used the two USB locations for switched power, and as far as I can tell I haven't touched the wires or connectors that run to the immobilizer antenna. I did originally tap the headlight assembly ground, but I moved that connection to the USB ground as well and the error persists.

I did talk to a professional who suggested I may have increased the load on the wrong circuit somewhere, and that it wasn't actually a true short circuit, just an ECU interpreting the wrong resistance as indicating a short. That suggestion is what prompted me to change my ground tap from the headlight harness to the USB accessory ground in the dash. Could it be that the (now removed) positap has permanently changed the resistance in that circuit by splitting the ground wire? Would a clean splice fix it?


Here are all the details:

I installed a relay and a controller, sold by the same company as a pair. I'm confident that I read their instructions correctly because the lights work as intended.

Attached is a photo of all the relevant connections I made behind the dash. There are three posi-tap connections made between the controller and the bike: The hi beam signal (white wire), switched 12v (red half of USB), and ground (black half of USB). There are also two yellow wires w banana plugs that go thru the stem to the relay, which is behind the plastic panels that hide all the wiring. The relay hot went directly to battery positive, the relay ground went directly to battery negative, and a shorter relay ground went to the frame (I did not see that there is an official engine block ground until after reassembly).

20210930_161610.webp
I suppose it's possible that when I pulled the yellow wires up through the stem I pulled an antenna wire out of its plug or connector?

It seems unlikely that on a bike this new the antenna would fail at exactly the same time as this install, so I must've caused the problem. I would appreciate any ideas.
 
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