Hi guys, I have a 04 trailblazer I'm working on for someone and it'* been in my shop for a month now. She had me tow it to my shop because it cut off while her daughter was driving it and it would not start back up. That'* all the details I could get. I have a wiring diagram for the starting system and Im confused with the neutral safety switch circuit because they use 2 yellow wires and lots of pink wires and I'm not sure which ones I'm supposed to be looking at. I am not getting 12v to the dark green wire going to the pcm though. I am getting 12v at the purple wire from the distribution box to the pcm

I am confused by you.......does the vehicle crank over and not start, or it doesn't crank at all?

If it cranks, and doesn't start, have you checked fuel pressure and spark? Will it start if you spray carb cleaner into the intake?

If it doesn't crank, do you feel the starter relay click, when the key is in the crank position? Have you jumped the starter relay to see if the starter cranks over?

Have you scanned it for codes?