Good. Now you know everything after the relay works fine. You've eliminated battery, starter motor, wiring, etc. It didn't start because that requires the key for security.

Then, move on to the rest of the system ...
Next time it's not starting get a test light or a multimeter. Ground the negative, and put the positive probe in hole 86. You should get power there when the key is turned to the crank position.

then move onto the ignition switch ... etc.

At this point I'd find and print out a schematic to follow. You can get one on charm.li
By the way you didn't post your vehicle info.

Unfortunately you can't really get away from "screwing around" when you're trying to locate an electrical problem. People charge money because they know what exactly to screw around with.

 

Okay! One other thing that happened earlier today...the first time it would not start. I fiddled with the batt cables, then got into the cab and turned the key...nothing...turned key again...nothing. The third time, it kind of hesitated, and then started. The second time today that it would not start after shutting it off, I tried the remote start...just for grins. That did not work either.

 

hm... if the remote didn't work either, then that could rule out a bad ignition switch. Things get pretty technical from here. Not something that can be taught easily on a forum.

 

Well dang the bad luck. I hate to take it to my local Chevy dealer, because they don't seem to have really good people there. Last time I had them work on a tranny issue, it took 6 visits, because they kept replacing the same part and it kept failing. I told them to look for something causing that part to fail...and they found a bad servo of some kind. They don't really troubleshoot, just start replacing parts...

 

I wouldn't go to a stealer either. Find an automotive electrical specialist. or just someone with a high level of diagnostic and electrical troubleshooting experience.

 

Roger that...not sure there is anyone around here with that expertise. Are the ECM and body control modules in this chain? Just curious, I can get both for less than the cost of the diagnostic fee at the dealer? I tried to find info on failures for these modules...as in what happens when they fail...can they fail and then work...but cannot find anything.

 

the ECM is involved. Everything is described in the service manual link I gave you (charm.li)
no. installed & programmed it will be over $1k, with no guarantee it'll fix the issue, which would leave you back at square one.
gambling on the parts cannon almost always ends in disappointment.

you're getting ahead of yourself. next step is to look for the start signal on the relay like I suggested.

 

I did the relay test with the jumper wire as you suggested....and the engine turned over fine. I know gambling on parts is a crap shoot, I am just really frustrated with this being so unreliable. My hobby is restoring old British motorcycles, but they don't have all this electronic crap to deal with!

 

I will keep my Fluke in the truck for next time it craps the bed, and do that second relay test you mentioned.

 

I thought I had posted vehicle info...2014 Silverado 1500 LTZ, 5.3l 4x4.