No start? check in here.

[j91z28d1]

some files that might help with no starts, I see threads all over about when these hybrids don't start and there's just so many reasons.

nothing about these crank like a normal car. the learning curve is kinda brutal if you haven't been into trouble shooting electronics in newer cars for a decent amount of time.

plus most dealers and shops techs aren't willing to waste their time on this stuff. they will mostly run up your bill till it's more than the truck is worth and leave you with a no start and a recommendation that you need yet another high price part that is probably discontinued anyways.
so hopefully this can help at little bit.. along with a good bi- directional scanner. like a tech 2.

 

[j91z28d1]

just to add to the no start.. one of the harder things to track down seems to be loss of isolation of the high voltage. it can be anything as small as the wrong oil used in the ac system by a mechanic that doesn't know electric compressors. the standard pag oil gets conductive over time. so you gotta use poe. also the main orange power wires are run in conduct to protect them, but it is possible they have been damaged and lost isolation. at any point the truck sees that some place it's not supposed to be, it will not close the contacts and you're dead in the water. since the 300v is what cranks the engine over.

because it's hard to track down, gm released a tool that will simulate the high voltage inverter or the drive motors depending on which part of the troubleshooting tree your at. it's called a EL-48458, they used to be very expensive new, but all over ebay for under 100$ these days.

here's a short walk thru of hooking it up.