Good with wiring? NEED HELP!

[Dyl510]

Just finished what I thought were the last steps on replacing the chassis wiring harness on my project, turns out I was wrong , so to save me from my insanity I'm hoping there's someone here far better with wiring than I am who can read my home-made schematic and tell me where I've gone wrong!

Pretty simple wiring, battery power is routed directly from the positive terminal to a "distribution bar" as I call it (it's simply a solid strip of brass with a 12v connection, and then a bunch of feeding terminals). From the terminals on that bar 12v power is distributed to switches and relays (one example is shown in the schematic).

The problem I'm having, the second I connect the ground on the battery and the system is hot, my battery voltage drops to below 1 volt.... so there is a major draw and/or short somewhere in my wiring.... I have to have something wired wrong!! Can you help?

[Selectron]

Hi, welcome to the forum.

One end of the distribution bar is fed from the battery positive terminal. So far so good, but it looks like the other end is grounded, which it shouldn't be, because if that's a solid metal bar then that's a dead short-circuit so that will be the problem. If it's grounded via a lead then remove the lead, or if it's grounded by being bolted to chassis then it will need to be unbolted and mounted on an insulator. And if you're not going to have fuse protection upstream of the distribution bar then I hope you do have protection on the feeds downstream from it.

[shorod]

I agree with Selectron, the only issue I see is that ground designation for the distribution bar. Also, to avoid a fire you NEED to have a fuse of appropriate current rating between the distribution block and the battery. If you find that after removing the ground from the distribution block you are blowing the fuse, then substitute the fuse for a test light. As long as the short remains the test light will glow at full intensity when the battery is connected.

I have a question regarding the light you are controlling. If that is a set of fog or driving lights, the relay is a good idea. However if it is a set of LED lights or other low current lighting, you don't really need the relay assuming the switch and wiring to/from the switch can handle the small amount of current the light would draw. No point in over-complicating the circuit if you don't need to. I'll also assume the relay connection going to the lights is terminal 87 such that the light gets current when the switch provides power to the relay coil.

-Rod

[Dyl510]

I knew it had to be something as simple as that! Cheers guys, thank you very much.

And yes there is a fuse box in the system, just didnt want to over complicate my windows painted diagram

thanks again!