GMC Troubleshooting Questions? Ask a Mechanic for Answers
That's a lot of data, but the computer is basically telling you that every injector control circuit is open.
My gut instinct here is that you need a new fuel injection control module (FICM). It doesn't even make sense for all of those codes to be accurate, it has to be a computer failure.
Please take the time to rate my answers, that's how I get compensated. If you have further questions, I am happy to follow up with you.
1. Check power and grounds to the Fuel Injection Control Module (FICM).
2. Make sure all the pin terminal connections at the FICM are tight.
3. If all OK then, replace the FICM.
I am attaching a schematic that will show you the power and ground circuits to the FICM.