Check Engine Light (Mil) not working (LS3)
 

I put a LS3 into my 71 Corvette with a GM ECM. The check engine light does not come on when I turn the key. I have the mil wire from the ECM to the light and a ground coming from the light. I read somewhere while I was trouble shooting that the ECM has the ground so do I remove the ground from the light? Thanks
Kevin

Rechecked the directions and it says the ECM supplies the ground for the MIL light. It says this circuit requires a 12 v low current light ( have it) and an ignition power source. So does the ECM wire go where the ground is on the light and a 12v power source to the light as well? Thanks

This is how mine was wired. One side of light (ground) was supplied from ECM and the other to a switched 12v source that is 12v+ when cranking and running.

Bingo it works thanks