Wiring in a new Circuit

[Son_of_Dog]

I've been trying to wire a relay into an existing circuit that is only powered while the bike is on with little success. I tried wiring the relay to close when there was power on the position light circuit, this caused the bike to have no tail light, presumably because the tail light is on the same circuit as the position light. I also tried wiring it into the starter circuit, which resulted in the bike not starting. I'm beginning to think that the relay being in the circuit is killing the circuit for some reason that I do not understand. Can anyone help me with figuring out how to wire in the relay so that I can have a switched circuit for my accessories?

[Tripps]

Way above my pay grade, but I know some guys have wired in an accessory block, a second set of fused connections

[1olbull]

Gage,
Have you reached out to DeCosse (Ken)?

[Son_of_Dog]

I didn't reach out to him directly, but I did post on the .net site.

[LabRat]

Gage, relays have a coil and set of contacts. You would wire one side of the coil to Negative and the other side to your Power On circuit. This would energize the relay coil when the power on circuit you wired in becomes hot. When energized, your contacts would close, completing the circuit to allow power to flow thru. You could grab power straight from the battery, with a fuse in line, to power one side of your contacts, then power your accessories from the other side of the contacts. Make sure you have a 12 volt relay. I’m not sure if this helps. I do HVAC work so it’s easy for me. I can walk you thru it over the phone if you want.

[Son_of_Dog]

I think that's what I did, but I must have had it wired wrong. Is it possible that the relay coil had enough amperage to cause the tail light not to come on?

[LabRat]

Coils draw very little current, it's the load across the contacts that you have to be careful with. If the tail lights are out then you must be tapping in to that circuit some how. Is that the Power On circuit you are trying to use for the relay coil?

[Son_of_Dog]

I wired the relay in the location shown on the diagram, in series. I plan to investigate my potentially bad wiring at lunch today.

[LabRat]

A little hard to see but if you are on that Yellow wire I think you are good for Key On power (the other side of the relay coil will go to ground or negative). You can verify you have power during Key On only by checking to ground. You should put a fuse inline before hooking things up, just in case you accidentally wire in a short. Blade type automotive fuses work well with standard spade terminal connectors. If you have the relay coil wired properly, you'll be able to hear the relay click when power is applied. If your brake lights are not working, you may have this connected across the Normally Open set of contacts, and not powering one side of the relay coil. Can you tell which part of the relay is the coil and which part is the contacts?

[Son_of_Dog]

Okay, I have looked at how I had it wired, and I've followed all of the direction posted above. The "signal" voltage is wired into the relay across contacts 85 and 86, which are the two that are connected to the coil in the diagram on the relay. I think there must be some kind of techno-wizadry happening in the ECU where it's seeing too much pull from the circuit and shutting it off? I'm not sure at this point.

I've reached out to Ken to see if this is something simple that I'm not grasping.

[Son_of_Dog]

Decosse was very quick to respond, and said that the issue is that I was wiring the relay in series, and that it should be wired in parallel. I'll be trying this this evening and will post results.

[Son_of_Dog]

Decosse's fix seems to have worked. He is the man!

[Son_of_Dog]

Here's what I learned from the great scot:

[Sparky]

Ohms law Rules🤣🤣🤣

[Son_of_Dog]

I will admit, his "off the top of his head" knowledge far exceeds my own, and borders on what I'm able to grasp conceptually. Pretty impressive stuff.