Article [13] ST1300 - Wiring diagram : Trailer Isolation Relay

ST Gui

240Robert
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I decided to draw a little wiring diagram with the correct color codes to make it easier.
That a really nice diagram. I won't be pulling a trailer but saved it because it looks so nice.

One question: is it necessary to fuse both leads from the battery? Is that because an isolator is involved? Is this isolator different from battery isolators that are supposed to allow two batteries to be charged independently (popular in high-output car audio systems the kidz did back 'in the day').
 
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Thanks to the OP im looking at buying a hitch as i type and will need to do this. Im always into never messing with the stock wiring of a bike and will always build an extension so i was gutted when i found out that the tail unit doesnt have a plug. This leads me to wondering the best way to wiring it on.
Usually i would strip near the plugs and solder on there release the pins heat shrink over the end and reinsert the pins but these sockets dont have pins?. do you just soldering then on midway and wrap them? Im looking to install led bulbs on the trailer and not use relays as it would concern me that if the relay fails im left with no trailer lights but maybe its better to put the relay
 
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Thanks for the diagram. But, electrical things give me anxiety....
I need help. I have a 2012 ST1300 and recently purchased a 1998 Bushtec Turbo 2 trailer. Picked up wiring kit from Bushtec.
When bike is on...trailer left/right yellow and left/right red are on.
When brake is not depressed both trailer red lights are on.
When I depress brake, both trailer red lights go off.
Blinkers flash correctly.
Red to switched power, white to battery negative (through a Denali Powerhub 2)
I have connected the harness blue to bike green/yellow (brake).
I have connected the harness green to bike black/brown (tail).
I have connected the harness yellow to bike light blue (right turn).
I have connected the harness brown to bike orange (left turn).
Any guidance would be greatly appreciated.
Kim

A member on this forum asked if I could provide him with some information on how to connect a Electrical Connection Trailer Isolation Relay on a ST1300.

I decided to draw a little wiring diagram with the correct color codes to make it easier.

For those who are not familiar with isolation relays, they act as a barrier between the motorcycle's wiring system and the trailer wiring. So anything can happen to the trailer, like short circuits, and it will not affect the motorcycle systems in any way. Some have them, many think they are not necessary. In any case, I sleep better knowing my trailer install cannot hurt the motorcycle's electronical systems.

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If anybody spots a mistake in the diagram or want to improve upon it, please let me know and I'll be happy to add your input.
 

Happy Rob

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Love this forum. I knew someone would chime in and help with a wiring diagram. Now I need to get a friend to help with this as it looks beyond my comfort level.
 

Obo

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Love this forum. I knew someone would chime in and help with a wiring diagram. Now I need to get a friend to help with this as it looks beyond my comfort level.
How many pins are on your trailer? These instructions are for 5 pin. Anything over or under that will require a slightly different setup that we can explain and draw for you.
 

Happy Rob

Rob
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Bought a wiring set up from local hitch store. Includes isolator. Not a big deal. Took a couple of hours, and all is working as it should. I'm almost ready for my first ride pulling a trailer!
 
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So much good discussion on these forums, but I have a few different questions. How and where did you route the wires and receptacle (plug) on the bike for the trailer connection? Did you come out from under the seat and over the fender, or somehow find a way down through the plastic above the wheel? What about water intrusion? Is there some neat way to tuck the connection plug out of sight when it's not in use? Just looking for some good ideas. Pictures would be very helpful as well. Thanks!
 

Obo

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So much good discussion on these forums, but I have a few different questions. How and where did you route the wires and receptacle (plug) on the bike for the trailer connection? Did you come out from under the seat and over the fender, or somehow find a way down through the plastic above the wheel? What about water intrusion? Is there some neat way to tuck the connection plug out of sight when it's not in use? Just looking for some good ideas. Pictures would be very helpful as well. Thanks!
I drilled a hole in the side under the case. Comes out down beside the ECU.
Not worried about water intrusion into the plug's female end when not connected, but you can buy covers for them.
Been over a year without any issues and I've been out in some fairly long and hard downpours when touring.

IMG_4709.JPGIMG_4708.JPGIMG_4745.JPGIMG_4743.JPGIMG_4744.JPG
 
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(Second pic in post above added)

More: The plug-in type of Scotch-locks and the wires all packed in behind the taillights.

I used a car-trailer harness with a built-in 5-wire to 4-wire converter to match the trailer.

The red and black taps on the red and white wires are to the brake lights in the topbox.

There are gaps between the tool tray and the bodywork, which is where the wires pass.

IMG_1980.JPG IMG_1981.JPG
 
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When I see these blue, so-called electricity thieves in Germany, my heart bleeds.
Yes, it works, but for me it would only be an emergency solution in case of a breakdown on the road.
If I would post such pictures in the Flyingbrick forum, the outcry would be huge.

holm from germany
 
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I don't disagree, but I have not had issues with them. It was hot, I'm still partly disabled, and they're fast.

I don't use them in high-current applications. All of the trailer lights are LEDs, so the current is very low.
 

Josh_ST

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I'm getting ready to roll my own isolation harness/relays, and was wondering if there's a factory junction for the rear lights I could interrupt and make my own sub harness. I hate modifying factory wiring unless absolutely necessary. I've searched through several trailer posts and haven't seen anything.

I've already got a "Hitachi" connector kit and crimper that I've used in several locations on the bike already, so I'm prepped to make my own splitter harness.
 

Sadlsor

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I'm getting ready to roll my own isolation harness/relays, and was wondering if there's a factory junction for the rear lights I could interrupt and make my own sub harness.
I wish I had taken more pics of my install, but a friend was helping and we were on HIS time, not mine.
Sad to say, I don't recall where / how we powered the trailer lights from the ST tail light. I'll try to look at it this evening between work and work.
 
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