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Wiring Trailer to Canbus

mike cousino

New member
Search = zip



Finally getting my hitch installed and need to wire to the plug. How did you guys
do it?

We have an '09 GS and because I have the Adventure rack, getting under the tail
section is a major task. So I've removed the tail light and can get to the wires
there. In testing I found the brake light wire has about 2.5v to it when the key is
on. When I hit the brake there is the full 12v.

I was planing to install relays, one for each turn signal and one for the brake light.
The tail light will run off the Centec. The relays will be triggered by the bike's light
and the relays will power the trailer lights through the Centec.

-Will the 2.5v cause the relay to chatter?

-I know Uni-go makes a wiring harness for the Canbus, it's over $100. Is itworth it
or should I just go ahead and make my own up?
 
The voltage going to the lights is a PWM signal (puulse width modultation) based on the selected duty cycle - that is why you see 2.5V as running lights and 12 when the brake ison, as that is the effective voltage due the meter measuring in RMS (average)

Your relay set up sounds valid, how does the Unigo harness address the issue?
 
Your relay set up sounds valid, how does the Unigo harness address the issue?

Thanks for the reply.

It doesn't address it, there are just wires to each light and a common ground. I
have both trailer and bike plugs.
I had the set-up on an '02 RS before, but only had to do a relay for the brake light
because of the link to the tail light could cause a fault.
I have a Centec and it's relay is triggered off the low beam headlight so it doesn't
come on 'til the bike is running. Have not had a problem there - yet!
 
Something you may want to try is one relay set with jumper to prove out your concept.

That way it is minimally invasive before going all out with the full install

Let us know how it goes - very interested
 
I have an 07 GT with Uni-go, searched all over for a isolater and the only company that had it was Twisted throttle. After being on back order for 3 months with no idea when they would recieve it from their supplier,I decided to hook it up without the isolater. A guy I met at a rally said he had done it on his 06 GT without any problems. I used one trailer tail light wire to the bike tail light, After pulling for 3000 mi. the only problem I had was the trailer bulb burned out. The bike gave me a message that the rear bulb was out , looked at the lights and both bike & trailer were not on. when trailer was disconnected the bike light came back on. I changed the trailer light to an LED and have not had any problems since. Before I had tried several automotive relays with no luck, when the key was turned on the relay would just buzz loudly.
 
I believe Bushtec has something for the canbus also.

Not sure about the GS, but the Bushtec unit for the RT is simply plug and play. It is fairly inexpensive (about $30, IIRC) and plugs into the the wiring harness just before the plug for the tail lights. You can (for another $25,IIRC) get a 5 to 4 converter unit if your trailer has combined brake/tail lights, which also plugs in....a totally plug and play arrangement. Worked so well on my RT, that I removed it when I sold it and it is now installed on my Goldwing.

Call Bushtec and talk to Samuel. bushtec.com
 
Call Mark at School house
He can tell you how to do it without a Canbus prob.

Ben

Spoke to Mark (nice guy) and ordered the three pieces: adaptor, isolator and
relay. Had to do away with the adaptor right away because it didn't work on
my '09 GS. The isolator's wiring diagram had the wrong colors so I had to figure
it out for myself. Then when I got it hooked up it blew fuses and the trailer relay
buzzed. I ended up putting the isolator aside as well and just using the relay. I
could've done the same thing with what I mentioned in the first post of this
thread and got the same results. I towed the Uni-go afor about fifty miles and all
seems good.
Because I had to remove the tail section to get to the wiring I didn't want to put
it back and have to do it all over again or leave it apart and lose a weekend of
riding. Removing the tail section with the Adv rack is a PITA.
I'll call Mark this week and see what he thinks is wrong. My guess is a defective
isolator because I was getting power where there shouldn't have been.
 
4 wire plug

most trailers use a 4 wire flat plug, you need to go to pepboys or salvos and buy a Hobbie 5 wire to 4 prong plug. just buy 16guage wire and stakon. like the ones plugged into the lights put 2 wires inside each stakon and extend the wires as long as you need em. left and right blinker, running light, brake light, and ground. I use good electrical tape and tape the wires neatly together and use black tie wraps to secure to the frame
 
Riding a motorcycle is a dangerous activity. Two Gold Wing riders in Wisconsin a few years back were killed when their trailer blew a tire and they crashed.

Pulling a trailer with a motorcycle is an additional hazard with which I do not need to deal.
 
Riding a motorcycle is a dangerous activity. Two Gold Wing riders in Wisconsin a few years back were killed when their trailer blew a tire and they crashed.

Pulling a trailer with a motorcycle is an additional hazard with which I do not need to deal.


Thanks for your insite, but so is riding two-up, but I do that too because my wife
loves to come along. I feel it's safer for everyone than her riding her own bike.

Now back to the topic, Wiring Trailer To CanBus!
 
2008 R12RT isolator problems- Need Help!

I have installed a Bushtec hitch on my bike. I have also purchased an isolator and sub harness to the wiring, a plug and play system Bushtec sells. The problem is that I can only get voltage from the yellow (right turn signal) wire. No other voltage is present. Bushtec has no idea what is wrong. I have replaced the plug and play with another isolater harness from Bushtec, but the same problem still exists. Any help would be appreciated.
Thanks in advance...
 
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