exactly. Be very careful working on these systems. Test lights are not recommended on these systems either.
HD-LAN (can bus)
Road Captain
Joined: Jan 2010
Posts: 709
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From: SO Cal
It was the 2014 Rushmore
Grand HDF Member
Joined: Jan 2012
Posts: 4,456
Likes: 2,859
From: Oklahoma
You have a serial data line which connects the transmission, speedo, security, turn signal cancelling and perhaps some other stuff. You still have real wires and switches for lights and turn signals. What are you working on or considering working on?
Stellar HDF Member
Joined: Dec 2005
Posts: 3,302
Likes: 274
From: Milton, Delaware
BE CAREFULL!
I attended a 'garage session' last month at the local dealer where they covered the new electrical system(s) on the new (2014) touring bikes. Although I don't have a new bike I still like to learn things. One of the things that they stressed was that the new system relies on resistance to cause voltage to be applied to the circuit, not directly applying voltage to activate lights and such. The new touring bikes use a BCM (body control module) that acts like an electrical relay (as opposed to a mechanical relay). Example: You hit your left turn signal button, the BCM senses a change in resistance from that switch, which then closes the electrical relay, sending power to the signal. The whole BCM is nothing but a black module about the size of a box of Dunking Donuts K cups, located under the seat.
They cautioned several times about splicing into power wires to add accessories as that changes the resistance and makes the system think there's a problem. This could cause many things from throwing a code to actually shutting the bike down. Adding a separate power source for added accessories is the suggested work around
They also stressed using dielectric grease any time the stock connections were removed or worked on as any water in the connection
would also change resistance.
I attended a 'garage session' last month at the local dealer where they covered the new electrical system(s) on the new (2014) touring bikes. Although I don't have a new bike I still like to learn things. One of the things that they stressed was that the new system relies on resistance to cause voltage to be applied to the circuit, not directly applying voltage to activate lights and such. The new touring bikes use a BCM (body control module) that acts like an electrical relay (as opposed to a mechanical relay). Example: You hit your left turn signal button, the BCM senses a change in resistance from that switch, which then closes the electrical relay, sending power to the signal. The whole BCM is nothing but a black module about the size of a box of Dunking Donuts K cups, located under the seat.
They cautioned several times about splicing into power wires to add accessories as that changes the resistance and makes the system think there's a problem. This could cause many things from throwing a code to actually shutting the bike down. Adding a separate power source for added accessories is the suggested work around
They also stressed using dielectric grease any time the stock connections were removed or worked on as any water in the connection
would also change resistance.
Last edited by Deucedog; Mar 29, 2014 at 11:09 PM.
Road Captain
Joined: Jul 2007
Posts: 570
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From: Left Ohio for the middle of no where in Fla.
I've been mod'ing my 2014 Ultra, the BCM might be a real PITA.
This BCM system is new, so I figure even the tech's aren't too familair with it yet.
All I wanted to do was add a tour-pak detach kit and add a flat lens style turn signal bar to the rear fender like the previous years had. Luckily since the Electra and Street Glides are pretty much the same, I was able to just plug the lights into the existing sockets behind the rear brake lens.
I'm getting different stories as to whether or not the BCM can be reprogrammed for the rear bar lamps to be turn & brake, turn & running or turn, running & brake.
I was told it would come from the factory as turn & running, it didn't it's turn & brake.
A stealer (I didn't buy it from) offered to check it all out.
This BCM system is new, so I figure even the tech's aren't too familair with it yet.
All I wanted to do was add a tour-pak detach kit and add a flat lens style turn signal bar to the rear fender like the previous years had. Luckily since the Electra and Street Glides are pretty much the same, I was able to just plug the lights into the existing sockets behind the rear brake lens.
I'm getting different stories as to whether or not the BCM can be reprogrammed for the rear bar lamps to be turn & brake, turn & running or turn, running & brake.
I was told it would come from the factory as turn & running, it didn't it's turn & brake.
A stealer (I didn't buy it from) offered to check it all out.
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Stellar HDF Member
Joined: Feb 2013
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From: Upper Providence Pa
Like was already mentioned, the one thing you don't want to do is splice and extend. I have heard of one who was successful with that and was fortunate enough to have obviously gotten lucky. The BCM is very sensitive to any or all changes that it is monitoring. Relays and additional power source is the way to go.
The OP never did say what he was thinking of doing...
01XLH, if you plugged into existing wire harness, and your turn and brake, the BCM from my understanding can not be reprogrammed to change that. If so it would change everything that runs on that group of wires. You made need to rearrange the wires in your plug. What are the part numbers and where exactly is it plugged in at?
The OP never did say what he was thinking of doing...
01XLH, if you plugged into existing wire harness, and your turn and brake, the BCM from my understanding can not be reprogrammed to change that. If so it would change everything that runs on that group of wires. You made need to rearrange the wires in your plug. What are the part numbers and where exactly is it plugged in at?
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Road Captain
Joined: Jul 2007
Posts: 570
Likes: 6
From: Left Ohio for the middle of no where in Fla.
01XLH, if you plugged into existing wire harness, and your turn and brake, the BCM from my understanding can not be reprogrammed to change that. If so it would change everything that runs on that group of wires. You made need to rearrange the wires in your plug. What are the part numbers and where exactly is it plugged in at?
The bulbs and sockets are only two wires, signal and ground, they plugged into 18A & 19A under the brake lens, as if it was a Road King or Street Glide. The hardest part was drilling holes into a Scoot with only 6 miles on it.
I also had taken the fairing off to install my XM satellite radio, which meant I had to remove the front turn signals.
When I 1st tried the rears, the bulbs flashed, but the dash turn signal inidcators flashed double-time. As I plugged the fronts in, the speed went back to normal.
Stellar HDF Member
Joined: Feb 2013
Posts: 2,325
Likes: 333
From: Upper Providence Pa
01XLH, check out this post, and got to # 5663.. You may want to ask him how he got his lights to be run/brake and do they operate as turn as well.
https://www.hdforums.com/forum/touri...today-567.html
Sorry, just realized his is a Rode King. Hmmmm I will look at that wiring for you
https://www.hdforums.com/forum/touri...today-567.html
Sorry, just realized his is a Rode King. Hmmmm I will look at that wiring for you