Hi guys. Has anybody traced the brake light wiring from the two tailights back, to locate where the individual brake light wires are connected together? I'm trying to put in a flasher to drive both brake lights from the single connection.
Brake light wiring
- Thread starter markchgo
- Start date
I tapped into mine for my flashing tail lights under the rear of the seat. Very easy to access, the wires run down the right side. I never understood why some people go through removing the tail light to access the wiring when its so easy to get to under the seat.
If you tap the wire under the rear part of the seat, one wire will control both bulbs. In that harness there are 5 wires:
-Tail
-Left turn
-Right turn
-Brake
-Ground
I don't believe there are any more wires, I'll try and check the wiring after I wake up. I think the plate light is wired to the tail light iirc.
When i added 2-way LED lights (2 functions for each light) I installed a terminal strip. I ran wires from the ground, left turn, right turn, brake, and tail lights to one side of it, to individual terminals. Then I ran the wires from my 2-way LED lights to the other. I installed my flasher unit (MC Larry's) in the same way. Now in minutes, I can remove the flasher if it ever fails; change from my lights working as tail & brake lights, to tail & turn signals; or turn signals & brake lights. I have them as turn signals & brake lights right now. No cutting, stripping, etc. needed to change the circuits, add, or remove anything.
Please excuse the messy wiring in the photo- I was still test fitting everything...but you can see the terminal strip to the left of the photo. To the right is the empty fuse block, which holds fuses for 10 circuits, and up to 5 relays, in a small package.
-Tail
-Left turn
-Right turn
-Brake
-Ground
I don't believe there are any more wires, I'll try and check the wiring after I wake up. I think the plate light is wired to the tail light iirc.
When i added 2-way LED lights (2 functions for each light) I installed a terminal strip. I ran wires from the ground, left turn, right turn, brake, and tail lights to one side of it, to individual terminals. Then I ran the wires from my 2-way LED lights to the other. I installed my flasher unit (MC Larry's) in the same way. Now in minutes, I can remove the flasher if it ever fails; change from my lights working as tail & brake lights, to tail & turn signals; or turn signals & brake lights. I have them as turn signals & brake lights right now. No cutting, stripping, etc. needed to change the circuits, add, or remove anything.
Please excuse the messy wiring in the photo- I was still test fitting everything...but you can see the terminal strip to the left of the photo. To the right is the empty fuse block, which holds fuses for 10 circuits, and up to 5 relays, in a small package.
Can you give us an idea where & what color the single "master" brake light wire is in that picture? I'm not the best at reading wiring diagrams but it looks like the wire should be green & Yellow??
According to my factory manual, it is green & yellow. You won't see the correct color going into my strip as I had to extend the Honda wires to reach. I just soldered on wires of the same size and soldered on the terminals on the ends. The harness I got the wires from is just under my terminal strip.
I just looked at the wiring harness and I don't see a way to access the green & yellow brake light wire without unraveling the part of the wiring harness that splits off and goes to the tail lighting assembly. Am I missing something?
I've got two things I want to tap into back there. The main wire to the brake lights and the wire to the license plate light. Planning on using the license plate wire for switching power to my auxiliary power relay.
The wires in that section are wrapped. Carefully split the wrap back a ways to expose the wires, pull out what you need, and wrap again with fresh tape. This is a lot more secure and out of the weather than where most people tap into them.
ST Gui
240Robert
Isn't the license plate light the tail lights? I thought there was just a cut out in the tail light lens to let it illuminate the plate.
Is this a special tape or do you just use vinyl electrical tape? I ask this because the adhesive on vinyl tape has a tendency to soften with time and heat which allows the tape to pull away.
Actually, now that you mention it, I'm not sure whether there is a dedicated light that shines down on the license plate or not. I may be misremembering but seems that's what I tied into on my ST1100s. To put it mildly, my memory ain't what it use to be.
Use a good quality tape, not that 25 cent a roll stuff, where the adhesive softens, and the vinyl hardens, over time. I use quality 3M tape and make sure the ends have a full wrap over itself to ensure it has a good clean surface to stick to. If its good enough for the OEMs, its good enough for me.
For temporary or throw away uses, use the cheap stuff. For long term use, don't save a nickle to spend a half hour on the side of road repair. 3M 33 Super (basic black) or 35 (colored). Pull it tight (just barley stretching) while wrapping, the tape has a memory effect and will try to revert back to it's original length.
Use 3M Super 88 when you need extra abrasion resistance. Same quality of adhesives but slightly thicker material.
Use 3M Super 88 when you need extra abrasion resistance. Same quality of adhesives but slightly thicker material.
Go with 3m tape.... I was always taught to stretch the tape while wrapping but follow thru the last couple turns without stretch... last couple of turns have no pressure to pull back.
The brake lamp circuit does use a Green/Yellow conductor, actually the circuit uses four Green/Yellow conductors.
The four Green/Yellow conductors:
- Front brake lamp switch.
- Rear brake lamp switch.
- Right-side brake lamp.
- Left-side brake lamp.
Photo of wire harness beneath seat cushions.
In the next photo (wire harness with the wrappings removed) the joining of the four Green/Yellow conductors can be seen at the 12 inch mark of the tape measure.
Photo of wire harness at Blue band.
In this photo the location of the four Green/Yellow conductors can be seen, the connection is wrapped with blue tape.
Photo of connection.
ST Gui
240Robert
A nickel or a few cents more is cheap insurance, and knowing there's a betters version of tape that I've used in the past is reason enough not even to bother with cheap stuff. I would never use so much of it that saving a few cents would amount to anything.
I'll start looking for v.33 and v.88.
I've always done this with electrical tape, but using cheap stuff, it didn't matter all that much.
Oh boy. I was thinking that there was a single switched brake light wire that came out of the harness, which then was connected to the two brake light wires in the tail light.
Is there a single switched wire that feeds both rear brake light bulbs somewhere?
Given that all four wires are joined together, they can (at least electrically) be considered as one.
What is it exacty that you'd like to do?
I think the two key things I notice with the 33 over cheap is it's ability to conform to the wires and that when you remove it in the future it doesn't leave an ooey gooey mess behind.
Hook up a Kissan brake light modulator to the brake lights ( https://www.kisantech.com/index.php?cat_id=3 ) and hook up the lights on my Givi tail trunk to this circuit.
Unfortunately Kissan doesn't make an individual flashing light bulb like they did for the ST1100 so I'm forced to use their little device that hooks in line to the brake light circuit. It only has 3 terminals... In, Out & Ground. That's why I want to stay with one "upstream" master brake light wire before everything splits off.
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