Tapping into brake light

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mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Tapping into brake light

Post by mercator1 »

I think I'm going to put the red 75 LED one of these on my new top case and run the 2 wires into their 3-wire converter so that I can run them at 30% intensity as a taillight and 100% as a brake light.  Plan to connect the 3 wires to some kind of quick connect to make removal of top case easy.  On the bike end of the connector, one wire will run to a ground, and then one to brake light and one to taillight.  Since all the wires under the seat are in a fabric loom and harm to trace, can anyone provide any insight as to the easiest place to tap into brake and tail lights?


Actually, now that I think about it, I had planned to get a PDM60 for horn and driving lights, so the taillight lead could just run to there (1 amp setting), I suppose, and I'd only need to tap the brake light.

BTW, I'm a complete wiring idiot.

http://www.customdynamics.com/truflex_flexible_led_lighting.htm
Last edited by mercator1 on Sun Nov 01, 2015 4:35 pm, edited 1 time in total.
guest3074

Re: Tapping into brake light

Post by guest3074 »

Under the pillion seat is the large round connector for the topbox (if you have the electric locking option) I think from memory its the grey with black wire that is the brake light.
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

Benchmark wrote: Under the pillion seat is the large round connector for the topbox (if you have the electric locking option) I think from memory its the grey with black wire that is the brake light.
No, I don't have central locking, which is why I can't use OEM LED case light. I'll need to tap somewhere else.
guest3074

Re: Tapping into brake light

Post by guest3074 »

mercator1 wrote: No, I don't have central locking, which is why I can't use OEM LED case light. I'll need to tap somewhere else.
I don't have locking but the connector is still there under the seat, sorry should of said if you have it's easy to identify the connector  ;)

My topbox brake light added by myself
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

mercator1 wrote: No, I don't have central locking, which is why I can't use OEM LED case light. I'll need to tap somewhere else.
Ah, cool.  Thanks.


Where did you run the wires in the box?  Looks like you could run them under the skin and cross the opening at the hinge side, and there appears to be an undrilled grommet on the right hand side that you could run thru the bottom of the box.
Last edited by mercator1 on Sun Nov 01, 2015 5:31 pm, edited 1 time in total.
T6pilot
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Re: Tapping into brake light

Post by T6pilot »

Think if you go to skene designs web. And click on P3 light install for 2015 RT you will find the correct wires
Jim
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

T6pilot wrote: Think if you go to skene designs web. And click on P3 light install for 2015 RT you will find the correct wires
Thanks, it looks like the gray/black is what I need to tap for brake light.  The other lead would go to the hot on my PDM60.  I appreciate it.


Anybody have a particularly good place to mount the PDM60?  Mount with heavy duty velcro?
guest3074

Re: Tapping into brake light

Post by guest3074 »

mercator1 wrote: Where did you run the wires in the box?  Looks like you could run them under the skin and cross the opening at the hinge side, and there appears to be an undrilled grommet on the right hand side that you could run thru the bottom of the box.
Sounds like you've got it sorted and planning on using the same route as mine  ;)
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

Benchmark wrote: Sounds like you've got it sorted and planning on using the same route as mine  ;)

With the lid off, I can see that there is a lip around the inner shell with little retaining tabs where the wires are intended to go around clockwise, and on the back right corner, there is a little clip that obviously directs the wire down into the bottom shell.  What I can't figure is how to run that wire in the lower shell so that it comes out that grommet on the bottom.  Maybe I have to completely disassemble the bottom shell also?  Unless I can figure out how to fish it with a coat hanger or something.
jbirdsaway2
Posts: 3
Joined: Fri Aug 21, 2015 5:40 pm

Re: Tapping into brake light

Post by jbirdsaway2 »

I can't help but weigh in on this... I'm literally laughing a little. I nearly went insane over a related issue recently (regarding you tapping into the tail light wire). I just installed a Power Commander V with the Auto Tune. It calls for 12V Switched Power. I visited every forum I could find, read every article I could find, and after making my wiring harness look like it had been attacked by a vampire, I finally found switched power that works (with a small annoying quirk I’m willing to live with). I started with the tail light wire… easy to get to. Brown is ground pretty much everywhere on the bike. So the striped wire was an easy tap with the posi-tap (first vampire fang mark of many). But……..pulling even the measly 5 amps made the CANBUS system shut down that entire quadrant. So, I would turn on the ignition and get power for a few seconds, and then the power to that whole section of the bike when dead, requiring me to toggle off the ignition and toggle back on to restore tail lighting. Simply unplug the posi-tap, and presto, power restored as normal. I tried tapping into the alarm wiring under the rear seat (still a hot wire, even though I don’t have an alarm system plugged in)… same thing. Zero power after few seconds. This went on and on… someone suggested pulling all the Tupperware off and connecting to the parking lights up front. What a stinking nightmare. Anyway, I blew off the forums and ended up tapping into the Aux power wire under the rear seat. It works fine. Only quirk (that I’ve now actually found in a couple forums related to this topic) is that when the ignition is shut off, the power remains on for the PC V and Auto Tune for several minutes before it shuts off. The draw is so little though, it never affects the subsequent engine starts. Anyway, thought I’d share. Good luck.
Last edited by jbirdsaway2 on Fri Nov 13, 2015 11:33 pm, edited 1 time in total.
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

jbirdsaway2 wrote: I can't help but weigh in on this... I'm literally laughing a little. I nearly went insane over a related issue recently (regarding you tapping into the tail light wire). I just installed a Power Commander V with the Auto Tune. It calls for 12V Switched Power. I visited every forum I could find, read every article I could find, and after making my wiring harness look like it had been attacked by a vampire, I finally found switched power that works (with a small annoying quirk I’m willing to live with). I started with the tail light wire… easy to get to. Brown is ground pretty much everywhere on the bike. So the striped wire was an easy tap with the posi-tap (first vampire fang mark of many). But……..pulling even the measly 5 amps made the CANBUS system shut down that entire quadrant. So, I would turn on the ignition and get power for a few seconds, and then the power to that whole section of the bike when dead, requiring me to toggle off the ignition and toggle back on to restore tail lighting. Simply unplug the posi-tap, and presto, power restored as normal. I tried tapping into the alarm wiring under the rear seat (still a hot wire, even though I don’t have an alarm system plugged in)… same thing. Zero power after few seconds. This went on and on… someone suggested pulling all the Tupperware off and connecting to the parking lights up front. What a stinking nightmare. Anyway, I blew off the forums and ended up tapping into the Aux power wire under the rear seat. It works fine. Only quirk (that I’ve now actually found in a couple forums related to this topic) is that when the ignition is shut off, the power remains on for the PC V and Auto Tune for several minutes before it shuts off. The draw is so little though, it never affects the subsequent engine starts. Anyway, thought I’d share. Good luck.
Rear lights use 5 amps?
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

So, gray/black is the brake light, and the brown is ground, which wire is the tail light?
pbooher
Posts: 2
Joined: Wed Sep 21, 2016 5:40 pm

Re: Tapping into brake light

Post by pbooher »

How about an update on your 2015 taillight wiring job.  What worked and what didn't?  I have a 2016 without locking and like the look of the Custom Dynamics led.
mercator1
Posts: 227
Joined: Tue May 19, 2015 4:58 pm

Re: Tapping into brake light

Post by mercator1 »

pbooher wrote: How about an update on your 2015 taillight wiring job.  What worked and what didn't?  I have a 2016 without locking and like the look of the Custom Dynamics led.

The install on my bike was very straightforward really. I started by taking the outer shell of the lid off to send out for paint. Ordered a spool of two conductor wire and routed around the inner part of the lid (you can see the path they have laid out for it). At the back right hand corner, at the hinge, you pass the wire down through a hole and fish it through the cavity in the wall of the bottom section, and out through the grommet in the bottom. I took the grommet out and used a weighted saxophone swab and tilted the case around until it fell out the hole in the bottom. I take the wire to the end of the weigjted string, and pulled the wire through the cavity.


I left about 12 inches of free wire and attached a quick connector that I bought off of eBay. On the other side of the quick connect I spliced in the part (don't remember what it's called) that splits off an extra lead so that you have a ground, hot, and a brake connection. This allows the LED to burn at 30% as tail lights, but go to 100% when you apply the brakes.


The hot and ground were attached to a auxiliary fuse block that also powers my air horn and driving lights. This wasn't necessary, but I like the idea of isolating accessory to its own fuse.


The quick connectors weren't necessary either, but I like the idea of being able to take the case on and off with minimal effort. I do have to take the seats off to get to it, and the guy at the dealer that actually hook the wiring up as I instructed, didn't quite leave enough wire from the fuse block. I have to really reach back into the space near the luggage rack 2 disconnect it. Still, a fairly easy thing to do.


It all turned out really well, and was fairly cheap, all things considered. As tail lights, the LEDs could be a touch brighter, but when you apply the brakes, they are super bright.


The flexible LED strip was just attached to that outside backing plate with the adhesive that came on it. No signs of it coming loose at all.


My only regret is that the wire distributor was out of black shielded 2 conductor wire, and I was in a hurry, so I just had them send me the wire with the white shielding. That 2" of visible white wire bugs me every time I see it.
Last edited by mercator1 on Sat Oct 29, 2016 2:43 am, edited 1 time in total.
pbooher
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Joined: Wed Sep 21, 2016 5:40 pm

Re: Tapping into brake light

Post by pbooher »

Thanks for the reply.  Where did you tap in for the brake light?  Did you use a relay to activate the brake light or tap directly into one of the existing brake light wires?
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