Brake Light Electrical Help Requested

What I'm trying to do:
I'm trying to wire a relay into the brakelight activation circuit so that I can wire my saddlebag lights as working brake lights without drawing too much energy from the OEM brakelight. I want the OEM brakelight to still work even if I don't have the saddlebages attached.

What I've checked:
(1) I checked the brake light fuse (fine)
(2) I checked the relay activation circuit and it appears to be getting power when the brake levers are engaged
(3) I've changed out the relay thinking that perhaps it have broken.

What I did:
(1) Under the right side cover, I found the three-wire circuit (red/blue/black).
(2) I spliced into the blue wire of the group so that when the brake lever is activated, the relay would energize.
(3) connected my splices to the relay at positions (85/86 so that relay will close when activated)

The issue:
The "running light" portion of the brake light is working properly, but the secondary "brake light" portion is not.

My assumptions:
(1) That the brakelight circuit is a 'double ground' circuit... meaning that power is supplied to both circuit using a single wire (red). The 'running light' portion of the brakelight is completed using a single wire (black). When the brake pedal is depressed, the second ground circuit is completed (Blue) and both circuits are fully energized.
(2) By splicing into the 'blue wire', I could get the relay to energize when the brake lever was engaged.

My problem:
The primary 'running light' circuit is working but the 'secondary' circuit is not.

Any suggestions?
Any corrections?

My Buco saddlebags have the four tailights wired as brakelights, to come on with the fender brakelight, and the outer two are also the directional signals. I didn't use a relay, just spliced them in under the right hand side cover. Been that way for over a year, no problems so far. From my experience, I don't know that you need a relay.

all i did when i hooked stb lights for her trunk was use a fuse ans used a connecter plug from a 955 triumph which is the same on the r3t not sure if same on the others and made my own wiring harness and so for she has had no problems dont know if this helps u or not

If it's ONLY the brake light you need from the relay try this...

To All,
Thanks for the suggestions...

I figured it out last night.

RatBoy said:

To All,
Thanks for the suggestions...

I figured it out last night.

Click to expand...

And........??? Man your worst than my wife....never finishes nothing!! LOL
I would be interested to hear if you kept the relay or not and why use the relay? I will be adding LED lights to my bags and other thatn the resistor inline i was just gonna do a nice and neat splicing job. Thoughts?

mutt

Kmutt said:

And........??? Man your worst than my wife....never finishes nothing!! LOL
I would be interested to hear if you kept the relay or not and why use the relay? I will be adding LED lights to my bags and other thatn the resistor inline i was just gonna do a nice and neat splicing job. Thoughts?

mutt

Click to expand...

Sorry KMutt, I didn't mean to leave you hanging, but I'm not going to bail out your wife... Actually, I haven't finished getting everything wired up as yet.

Anyway, I did leave in the relay, I had to change around how I was wiring it. Apparently, I could run the brake wire (blue) through the relay only... not enough juice through the circuit I suppose. So I pigtailed the brake circuit (blue) up to the relay, dumping it to ground. I had to do this because I couldn't get the relay to energize and the brakelight to work otherwise. (#85 - #86).

I going to run the brake light wire off of the bag tailight through the relay and dump to ground. I should get it finished up in the next couple of evenings, but considering it's supposed to near 100 degrees here the next few days, I may be a little longer.

When I'm done I'll post a wiring diagram to show exactly what I did.

As to the Why?:
The lights in my bag are incandescent. I didn't want pigtail off of the existing taillight circuit to run two additional bulbs, so I decided to wire the relay to open and close the brake light for the two saddlebag lights so that I don't overload the tail light. Considering the problems that I've had with the ignition switch, I felt safe was better than sorry.

If you are adding LED lights, their load is normally low and no relay is required.
Some LED assemblies today have added resistors to keep the blinking the same as with incandecent bulbs. Thes may need a relay, but may not. If you have any questions, ask the seller or manufacturer about the load - most have this available.

Ratboy - follow my diagram.

When you apply the brake the blue wire is acting as the trigger for the relay to operate (#85) - #86 needs to be grounded to operate the relay.

You need to understand that the blue wire is simply the TRIGGER and NOT actually carrying the load. The load is supplied by the fused 12v+ supply (#30) which is passed through the relay to #87 (the output) when the brake is applied.

As such, #87 becomes the 12v+ feed for your incandescent saddlebag lights when the brake is applied - don't forget that they will also need a ground (12v-).

Bandit

Good info fellas! looks like if I want to leave the tail light as stock than add leds in my bags, I can splice into the circuit and either by the led's with the resistor already wired in or the harness that comes seperate. Cool will be a good winter project. Weve had the best summer up here in the north and Im not taking the bike down for nothing if I can help it!!

mutt