How I made really good on/off signal wires

**Kovermours** · 03-12-2005, 10:39 PM

When I put my first car together nicely I made many many mistakes... but the first thing I did right is get the on/off signal wire right. I didn't necessairly want the computer / amps on just when the ignition was on, I wanted to control it all myself, and have some feedback about it. So this is what I did.

I bought a fuse adaptor at Canadian Tire (I guess if you're not in Canada you can get 'em at any old crap warehouse) which is a little plastic thing that plugs into a fuse socket in your fusebox. You can plug two fuses into it, one to replace the fuse where the fuse adaptor goes (so if you plug it into the interior light fuse plug, you'd use the interior lights fuse) and the second to fuse a line to something else... such as on/off signal wire. I plugged my fuse adaptor into the horn fuse because I found out it was always on.

After taking the wire and crimping it to more wire and running said wire to the cubbyhole underneath the center console armrest, I bought a marine busbar and made 1/2 of the terminals positive and 1/2 of them negative. One terminal was used to power the positive side of all the switches, of which there were five. Basically, all five switches were connected to the busbar on both sides, so that if I wanted to replace a switch because the lightbulb in it burnt out, all the terminals were right in front of me, in the center console.

The switches I used were found at an electronics store and were $10 each (cdn). They had a flip cover and a red light when turned on. Very James Bondish.

From the busbar the five signal wires were braided together to make them easier to hide and were run to the back of the car where the computer / amps were. I had another (smaller) busbar there that served the same purpose as the first one: if I needed to unhook something, it was right there in front of me, and I didn't have to fiddle with removing side panels to remove wire.

So that was my first project car (1983 Mustang). It was cancelled when some asshat smashed into it. I have a 1985 Tercel now ($100!) that I'm going to be fiddling with. Look forward to a Phoenix Gold 5-channel amp, two 3.5" + two 6.5" in the front, two 6x9" in the rear, a 10" sealed sub, and of course, a computer, and some awesome on/off switches.

**RedGTiVR6** · 03-13-2005, 08:41 AM

sounds very similar to what I have done:

**Kovermours** · 03-13-2005, 11:57 AM

Yes, it looks very close. That busbar looks a little big :-)

Did you do a switch array like I did or is it all ignition-controlled?

How did you get fused power for the switches?

Maybe I can use some of your ideas in my new project

I'd like to add that because this was signal wire, I used simple 20g wire for everything, with simple butt joints or clips if they needed to be disconnected. The larger wires are used for powering amps and computers and such and need to be much bigger.

**Lucky** · 03-13-2005, 12:31 PM

Would it be possible to do use the fuse adaptor and plug it into the central locking fuse then connect it up to a signal wire so that when the car opens it gets a signal?

**Kovermours** · 03-13-2005, 05:49 PM

opens as in opens the door?

there would have to be a fuse that gets power when the door is opened

if you mean when the car is turned on, my cigarette lighter fuse was only on when the car was on accessory

just play with your fuses until you figure which one is on and when

easy :-)

**RedGTiVR6** · 03-13-2005, 06:07 PM

Originally Posted by Kovermours

Yes, it looks very close. That busbar looks a little big :-)

Did you do a switch array like I did or is it all ignition-controlled?

How did you get fused power for the switches?

Maybe I can use some of your ideas in my new project

I'd like to add that because this was signal wire, I used simple 20g wire for everything, with simple butt joints or clips if they needed to be disconnected. The larger wires are used for powering amps and computers and such and need to be much bigger.

lol - the bus bar has constant (yellow), ignition (red), and a remote turn on (blue), and ground (black)

fused power for what switches? I'm not running a bunch of switches, that's why I mentioned it was similar to your set-up...=]

**Kovermours** · 03-13-2005, 06:15 PM

A-ha :-)

I wast first considering a system similar to yours, but then I would have had to run wires to the rear of the car, and then back to the center console - the way I have it set up, all the components are up front and easy to see and work on.

Everything is going to be harder with this Tercel - it has no center console, which means ripping the dash apart and putting all the switches in there. Fortunately there is far more room underneath the door sills to run many bundles of wire.

What do you use the three states for? I wanted everything to be run on switches so I could say turn off an amp if I didn't need extra noise or turn off the computer if I just wanted radio.

**Kovermours** · 03-13-2005, 06:22 PM

Looking at your cardomain page more closely, you ran a grounding cable to the rear of the car. Why did you do this? I thought that the frame was the best ground possible, because the mass of metal acts as a capacitor and can act as a better ground than a cable. Unless for some reason the rear of your car is isolated electrically from the front.... like you got chopped in half...

**Lucky** · 03-14-2005, 07:41 AM

Originally Posted by Kovermours

opens as in opens the door?

there would have to be a fuse that gets power when the door is opened

if you mean when the car is turned on, my cigarette lighter fuse was only on when the car was on accessory

just play with your fuses until you figure which one is on and when

easy :-)

Well whenever I open door for example a light on the door automatically turns on - so I could use that as the fuse right?

Thanks

**RedGTiVR6** · 03-14-2005, 08:04 AM

Originally Posted by Kovermours

Looking at your cardomain page more closely, you ran a grounding cable to the rear of the car. Why did you do this? I thought that the frame was the best ground possible, because the mass of metal acts as a capacitor and can act as a better ground than a cable. Unless for some reason the rear of your car is isolated electrically from the front.... like you got chopped in half...

It has been proven that on average the chassis of a car acts as no more than a 4gua cable...

I'm running 1/0 for power and ground. I also did it this way so that there would only be ONE grounding point - the battery. This way I wouldn't have to deal with different gounding points and ground loops and all that jazz....

Not sure on your previous post before this one....who were you directing it all to?