And make sure you have that heat shield over the starter solenoid that snaps in place. It's there for a reason.. .. to prevent exactly what you're describing

 

Item number three in the below picture. It snaps in place over the starter solenoid

 

Good point Robert. Folks often forget those during replacements or think they don't matter. Auto MFGs don't add things for no reason.

 

Hey, do you mind sharing what your solution was!!


QUOTE=jstdoitt21;413075]Hey Hummer family

i’m having a problem with my H2 with only 43,000 miles on it. For some reason you get inside start her up, Drive, park somewhere get back in and It won’t start. It’s got full power but won’t start if you wait 20 to 30 minutes it’ll start back up.

I’ve done everything everybody’s recommended. I’ve disconnected the Onstar , took the Onstar fuse out. I’ve checked the alternator. I purchased a new battery, etc. etc. when I take it to the auto shop, they say oh we cant reproduce the problem of course.

Has this happened to anybody, and if it has, how did you fix it or does anybody have any recommendations how to take care of this problem because it’s left us many times waiting, won’t start and I have a newborn and I need the Hummer to be reliable or my girl wants to get rid of my baby.[/QUOTE]

 

@arabago
The article in the link below comes to mind, perhaps a bit more feedback from you would help, e.g.

• what model year?
• is there a MIL or any codes?
• does it crank?
• is there a "click" from the starter solenoid?
• have you checked the grounds and starter connections ?
• do the lights dim when the key is turned?
• if your battery has side-posts are the 2 battery terminal screws in good condition?
• is there any aftermarket stuff, e.g. alarms or other equipment such as radios or remote start?
• is only when the engine is hot ?

There is a "Crank Relay", CRANK FUSE(10A), IGNA (40Amp), IGNB (40Amp) and IGNE(10Amp) fuses (all in the fuse block under the hood) perhaps a bad connection?
There is also a Park/Neutral Switch on the left side of the transmission.

Not sure what happens by waiting, however your comments e.g. "alternator" suggest a battery related problem?

The Power Train Control Module activates the Crank Relay when the key is turned, not sure if there is a key security alarm type disable or any other sensor that could block the PCM.

https://www.700r4transmissionhq.com/...h2-wont-start/