My marker lights are LED, very little power draw. . .unless it can be programmed at the dealer there's no way that I know of to do that. I turn ACC on, and only the marker lights come on . . . fine for me.
I did ask the dealer any they said it can't be programmed... It's not a big deal, but I'm surprised there's no way around it. It doesn't come up often, but usually on trips we'll be sitting outside the hotel having a few beer and put some tunes on, and I don't want to kill the battery any faster then I have to. I did read in the manual that it will automatically shut off after two hours.
It looks like the side marker lights are connected to the accessory circuit. connector 12A - V/BE wire. If you connected them to the BE wire connector 12A then they should just stay on with the tailight
I'll have to double check what lights stay on, but i think it's everything on the tourpak. I guess it would be possible to rewire the power source to it, but I guess it's not a big enough deal to start cutting into the wiring. I'm really surprised that there isn't an option for the dealer to program it, similar to selecting the passing lamps to stay on with high-beam headlight... Thanks for checking out the wiring diagram though!
On my 14 FLHTK, the side markers & the power port (inside the tour pak) stay on with the Accessory position. From the wiring diagram, the same V/BE wire brings power to both. I never looked under the tour pak liner, buy maybe it's an easy mod.
I'm sure it should be relatively easy, just depends if I want to cut into the wires. Next rainy day I'll pull a few parts off and see what would be involved.
It is an option in the diag4bike configuration, I can't imagine it is not available on the dealer technician tool. I think your dealer is unaware it is in there. Mine was off from the factory on my 2014 street glide special, no lights are on in accessory except the radio and speedo lights.