- Joined
- Apr 15, 2009
- Messages
- 11,527
In my wiring adventures I'd never thought to use a switch to go to ground. But then I got stumped by the Domino switch on the Ducati. Since it's aftermarket and would look nice on a Norton I thought I'd include my learnings here. What threw me off is that I have a custom motorcycle circuit board that just has SPST relays and I couldn't get the horn to work. And I was scratching my head trying to figure out the kill switch (there, I said it, suck it up).
It wasn't until it dawned on me that I couldn't use those relays and would have to use other ones to make both these item work. The SPST relays were linked on the board so I couldn't isolate the grounds for the switches. I'm sure someone will tell me I'm wrong.
The horn button grounds out when you press it. I kept expecting 12v at the horn button and no matter how many times I pressed it that never happened.
By using a different relay I can use the 86 to ground (from the switch), apply power at 85 and 30 and have horn noise come from 87. I'm using some Hella relays and for some reason they didn't like those numbers and just use 1-5. Germans... :?
On the kill switch when you press the button the two wires connect. You can imagine that this made my head hurt. Here I'll ground 86 and apply power to 85 (both through the kill switch), 30 will be fused power and 87A will have power to the ignition box until the kill switch is pressed (then it will flip to 87 and no power at the ignition).
How did I do? And yes, this is negative ground.
It wasn't until it dawned on me that I couldn't use those relays and would have to use other ones to make both these item work. The SPST relays were linked on the board so I couldn't isolate the grounds for the switches. I'm sure someone will tell me I'm wrong.
The horn button grounds out when you press it. I kept expecting 12v at the horn button and no matter how many times I pressed it that never happened.
By using a different relay I can use the 86 to ground (from the switch), apply power at 85 and 30 and have horn noise come from 87. I'm using some Hella relays and for some reason they didn't like those numbers and just use 1-5. Germans... :? On the kill switch when you press the button the two wires connect. You can imagine that this made my head hurt. Here I'll ground 86 and apply power to 85 (both through the kill switch), 30 will be fused power and 87A will have power to the ignition box until the kill switch is pressed (then it will flip to 87 and no power at the ignition).
How did I do? And yes, this is negative ground.
