Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
HI there, I am Cam. Sorry to hear about this issue.When this happens, you loose all battery power, so no locks, lights, anything at all?How often does this happen?
There is a common issue on these that might be the source of your issue. Behind the battery on the firewall is a mega fuse. The battery cable runs in there and its possible the nits of that mega fuse are slightly loose. If this happens it would loose all power. A picture of that is attached. This has been a the source of many power loss issues and it may even be worth changing this fuse if you are uncertain about it. It’s a 175 amp Mega fuse.
If this is clean and tight then below is a list of things you need to check. - battery cables as they attach to engine ground- I know you checked the battery, but did you check it when there was no power? Simple meter reading could tell us a lot. -loose fuse block or corrosion in there.