Trailer hitch K1200 GT nextgen.

[tordams]

I have a 2007 K1200 GT, and would like to buy a Unigo trailer ( they can make a trailerhitch that fits the bike) but have no solution for the lighting.
My BMW dealer i Norway can not help me either. There has been suggested that I have to use isolation/bypass relays so that the can-bus system is not disrupted. Does anyone have a suggestion how this can be done. My Autocom gets power from the 12 v auxillery output.

Best regards Tor Damsleth
Norway

[messenger13]

Yes, you should install a relay-controlled fuse-block. Then you will have available circuits for lighting, or what-have-you. Below is my crappy schematic for what I did to power one of my fuse-blocks.



http://home.alltel.net/paulsey_dsl/messenger13/Relay.jpg

[RVB1019]

The blue wire in your diagram would then go to whatever you had to power right?

Then if I wanted to run my Motolights or whatever else, I would then have to run another relay?

[meese]

The blue wire in your diagram would then go to whatever you had to power right?No, the blue wire is the trigger to turn on the main relay (and thus power up the whole fuse block).

Any accessories would be wired to the fuse block using the appropriately sized fuse for the item being powered.

[RVB1019]

So the blue wire would go a switch (autoswitch or other).


Thanks!

[meese]

The blue wire goes to a signal source that is active when the bike is on, and dead when the bike is off. That could be the parking light up front which is on when the key is on, or the low beam feed which only comes on after the engine starts running.

All Joe's diagram does is show the wiring for installing a separate a fuse box that is outside the CanBus system and is powered up automatically. Any accessory lights, radios, intercoms, horns, etc. are wired to the new fuse box, but none of that is shown in the picture above.

However, it doesn't address the original question about trailer lighting. To allow for running (tail) light and brake light connections without upsetting the CanBus, you need a relay isolation package like this one (http://www.bushtec.com/relay.html) from Bushtec (http://www.bushtec.com/) or the one mentioned on the bottom of this page (http://www.dauntlessmotors.com/hitch-pages/bmwk1200lt_hitch.htm#Four%20Isolator%20Bosch%20Micro%20Relay1) from Dauntless (http://www.dauntlessmotors.com/). It will use the existing bike wiring to sense when the tail lights and brake lights are on, but will power the trailer lights directly from the battery.

I also see an isolation relay listed here (http://www.schoolhousemcacc.com/product_info.php/products_id/78?osCsid=027847fb655c7cd10aec289ba537901e), but I'm not familiar with that company.

More info can also be found in this thread (http://www.bmwlt.com/forums/showthread.php?t=32467) in the Trailers, Sidecars, & Trikes (http://www.bmwlt.com/forums/forumdisplay.php?f=86) forum.

Adding a separate fuse block is a good idea, but is a whole different discussion than trailer hookups.