Preshr

I had a shop do my 60 to 80e swap. The ECM stopped responding when the tuner was tuning it. I used the harness that does not require a segment swap. They have put a couple different Ecms in the truck and it still will not even crank over. We got a used ECM and had the dealership load the stock tune in. You can upload a tune but cannot do any diagnostic tests. I drove the truck to the shop so I know it was fine when I dropped it off. Is there a body modual or something else that could be causing this? Could this be an issue with a crossover year truck?

Details are in my signature.

chris99gmc

Even if you do the relays for the shifting of the solenoids, I still think you need to add the pigtail and sensor for the extra speed sensor. I could be wrong tho. It's been awhile for me... Also double check the fuses(ign 0?) and the gear switch indicator alignment and wiring.

I'm just throwing some things out there, Bc you have given limited info. You said it won't crank over. But does the started try to engage or you can't hear the starter at all? Does the trick have any codes or security light on the dash?

1FastBrick

iTrader: (17)

I am guessing Pinched or Broken wire Near rear of the engine. Probably the ground wire when the Trans was swaped.

Preshr

Just to claify, by " will not even crank over" I meant that the starter relay does not click and that I assume that it is not getting the proper signal from the ECM allowing it to start. I will ask the tuner about the speed sensor issue. They have checked several times for pinched wires and haven't found anything.

Is it possible that it could be from tack welding the crossmember during fabrication?

As for the lights on the dash, I'll have to ask the tuner that also. My tuner is about 2 hours away and is keeping the truck right now.

Preshr

Just an update. You win. It wasn't the ground but the 12 volt reference wire to the crankshaft position sensor was cut in 2 along with a couple others that were pinched.

Like I said in my first post, I used the harness that doesn't require a segment swap. Does anyone have any tips on how to manipulate the 60e table in the tune so that the converter will tighten up between shifts? Right now, it shifts through all 4 gears and wont pull itself up a hill, the converter just slips.
Circle d 32-3400.

06murder

All you have to do is switch brown and white wires, but leave white wire out, you don't need it and run vss, wires for Speedo. And get segment for your ecm, reflash and test drive, I didn't buy the harness most ppl dont.lol anit worth the money to me.