Did not read through the entire thread, but recently had the same problem on my '19 SGS. The trouble codes indicated it was the right handlebar switch pack. Further investigation by the local dealer tech determined it was not the pack, but a fault somewher in the wire that runs from the switch pack to the ECM for the Kill switch. I did not want to waste the Techs time, or my wallet for labor charges, to search for the fault so I took it home and removed the fairing. When tracing the circuit, a small connector located just below the radio fell apart in my hand. Pushed it back together and...you guess it... the security light went out. Put the Fairing back on, cleared all the codes and all has been good ever since.

I don't know if I caused the loose connection when I changed my Handlebars, or if it was that way since I bought the bike. However, it just shows how careful one must be to make sure all the connectors are put together fully after doing work on our bikes.

Security light staying on is most likely associated with faulty wiring. I have had it staying on after switching to LED's(resistance too low), or with the exhaust servo eliminator plug getting water in it or with the air cleaner eliminator switch not being on or getting moisture. On a 96 TC switched the air cleaner and it was fine without the light coming on. Either it was short circuited or not working as stock.

Your best option is to start by the places where you know the harness has been altered. Bought a Street Glide just now which has an Arlen Ness package whatever that means and guess what the security light came on and it does not have a security system yippee. LED's all around, RSD air cleaner, unknown pipes...

My blinkers go three times normal then fast so my bet is on the LED's. With LED's cheapest option is to put a resistor on each circuit. Load equalizer is way more expensive than 2 buck resistors.

My tail like is half lit along with license bracket longer which
 

my red light is coming on and staying on also and I went out to get my food delivery noticed my led tail light half lit up and the relocated license plate bracket light is also on the shop must go a wire mixed up when they installed the stage 2

Vernal,
This is an old post but to let you know it help me out..You save me alot of money going to the harley dealership wow! Thanks bubby!

Floyd

:icon_that:

Vernal knows Harleys, especially the electrical stuff.... where I am admittedly weak....

Anytime and electrical thread pops up, and Vernal makes a post, I usually end up taking notes...

July 10 2023
2018 STREET GLIDE SPECIAL.
Purchased this bike in Feb 2023. Today I installed a RAM perch mount phone holder on the right side, brake throttle housing for a trip coming up the 14th. Took a few short trips after the installation with no problem til the end of my errands and saw the security light solid red while riding, stopped idle, and engine off but power on.. Noticed rear brake lights and turn signals were not responsive nor were the rear hazards. Running lights were working. Cruise control did not work though I could turn it on. Went through DIAG etc blah blah blah. It dawned on me that the recent installation of the RAM mount is the only change i've made since March. I inspected the installation and noticed a gap between the brake control and the bracket in front. Didnt seem right to me so I re-installed the perch mount with shorter bolts that closed the gap. Now all lights and cruise work just fine. Seems very odd to me but I dont know electrical. Any ideas why this could be?

Hope someone finds this useful in the future.
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