Turn key lost all power

Ok, so I just got this DB1 and it had a side post battery in it. I was having a problem with the terminals not making good contact, so I replace the battery cables with the corect ones (but I left the extra ground, never can have to many!). After putting the correct battery in it, it was starting fine yesterday. This morring I jumped in it to go to work and when I turned the key, all the power went bye bye. The starter bearly bumped, all the of the lights on the dash went out, the seat belt would not retrack and the window will not go up. I can hear some sort of buzing noise coming from the passenger side under the dash even when the key is removed. I have checked all the fuse (under dash and under the hood). Any suggestion on where to start?

Check battery voltage. You have a multimeter? Or test light?

Battery is strong, 12.6 volts, just installed it.

i would try tracing all of your power wires starting at the battery to make sure you don’t have a loose or dirty connection any place. sounds like the same kind of thing that happens when your battery terminal gets loose or has corrosion built up on it. Best of luck dude.

Solid conection. In fact there is .02 ohms resistance from battery to starter, .04 ohms battery to fuse pannel, and .01 battery to ground, but it is showing 5 ohms from terminal to terminal. 5 ohms sounds kind off high to me.

What gauge cable did you use to run the starter motor?

OEM battery cable from my DA turbo project.

Hmmm. And youre absolutely sure ground is good?
Id Try voltage drop testing the starter circuit.
Testing resistance in a high powered circuit, like the starting circuit, is ineffective

[QUOTE=welfare;2226165]Hmmm. And youre absolutely sure ground is good?
Id Try voltage drop testing the starter circuit.
Testing resistance in a high powered circuit, like the starting circuit, is ineffective[/QUOTE]

There is power going to starter. I can make it roll over by jumping the ignition on the starter to the battery. There is still no power coming into the car.

By jumping the starter, al that’s telling you is that the starter is good. You’re bypassing the rest of the circuit though.
Voltage drop testing is the only effective way to test the circuit in action.
Have you checked the under hood fuses? The winged ones that screw into the fuse panel. If they’re not screwed in tight, it would also cause these symptoms.
Check those 2 fuse connections and if they’re good, start running voltage drop tests. It will show you where the problem lies

I have checked all the fuse. I even changed the main fuse out for the one that was in my other car that I know is good.