I put new battery cables on the truck (positive and negative, both batteries), I am absolutely sure that I have everything hooked up the way the old cables were, but now I have no power. No lights, no start. Cables are oem, just like the ones I removed.

Is there any breaker that needs to be reset, or anything else that needs to be done when re-connecting the batteries? Both batteries read 12.X volts. And had no electrical issues before, I just replaced the cables because they looked like they were corroded, and I usually replace the cables when I get a new (used) vehicle.

 

turns out I had the wires reversed on the starter relay. that was it!

 

I literally made an account on this just to tell you how much you saved my day. Just went through the exact thing replacing my cables and had no power at all after. Thought I messed something up! Turn out it was just like you said, mixed the starter relay wires. Thanks!!!!