Weird wiring problem

[Bm1912]

So I assume this is a wiring problem, I did an LS swap on my 97 c1500 and got it put back together and took it on it’s first test drive. I went to turn the lights on and nothing happened so I tried my brights and that worked. So I went down the road and came back. And turned the key off and took the key off and the truck was still running while the key was out. But as soon as I turn the headlights off the truck turns off like it’s supposed to. Any suggestions?

 

[nivlem7]

Sounds like you have somehow got the headlight switch output wired to ignition. If you have an ohmmeter, ring out from the switch to the ignition wire, and trace it through the connections to find out where they are crossed. Do you have a wiring diagram?