2008 suburban LTZ will not start

[Doug_Scott]

Remember there are two connections on every wire. Take a good look at the other ends of the battery cables, paying particular attention to the ground cable. Look closely at the crimp for any sign of corrosion. In the first stages of diagnosing this, forget about the computer part of it, and pay attention to the very basic systems. This is no different to diagnosing a no crank issue on a non computerized vehicle.

[ejstave]

I can jump the starter relay and it cranks just fine. I checked the grounds and the positive leads and found nothing strange.