WHAT I HAVE:

I recently blew my stock trans at 256k miles. My truck is a 1999 4r 4wd auto with Cali emmisions. I replaced the transmission with a 1996 4wd auto with federal emissions(I'm hoping the difference between emissions systems isn't the reason it's not starting). Before the trans blew, I didn't have any issues with starting.

PROBLEM:

I am not getting 12v to the exciter/signal wire for the starter after the swap.

WHAT I'VE DONE SO FAR:

I was able to get the truck started and running by jumping 12 to the black/white wire near the relay in the fuse box under the hood that's by the battery while the iginition is on. It runs fine and drives fine. It just seems that there is no signal going to the starter. I checked with my multimeter to confirm that when the ignition switch is supposed to be sending 12v down the exciter wire, it doesn't do the job.

QUESTIONS:

What exactly does the starter circuit look like?
How should I trouble shoot this?

WHAT I KNOW:

I know there's a relay in that fuse box for the starter. Does anyone know where the signal wire for that relay comes from? I was thinking it would be the ignition switch. Can anyone confirm?

Thanks in advance!

 

The neutral saftey switch wasn't plugged all the way in. I was able to pop the harness off without having to press the retaining button. I pushed it all the way back in until I heard the click. Tried to start the truck, and she fired right up!