The alternator tends to be an issue, as that was my problem. What stumped me was the replacement I got was bad right off the shelf. I took it back to AutoZone and they gave me another one. The first one looked brand new, but it was in a plain box and not taped up or anything, and the second one came in a labeled box and was taped up.

I think they gave me an old one that someone else brought in for their core replacement. It looked new, so it probably sat around, and someone didn't realize it was a core replacement is my guess. But changing that out solved all of my issues other than my radio. My screen is still black. I have purchased a new more modern radio with a larger screen but have not gotten around to replacing it yet. I hope to swap it out soon and if so, will update that here.

Another upgrade I did for mine that was really helpful was that I replaced the rubber seals that start at the front windshield and run along inside the front and rear doors. Mine had shrunken over time and as no longer sealing properly. I didn't realize how noisy the air seepage was until I replaced that. It really quieted down my ride. I went with a GM OEM part for that to be sure it fit, and it was not cheap, but worth the costs.

 

That happened to me a few years back after a battery change at Advance auto. The guy hooked up a battery charger to my leads while the battery was being replaced. A few mile latter when I turned the radio on ....BLACK Screen. And it knocked out the GPS in exact location reading. At some point the screen would turn on and you could see your were 50 to 100 feet from where the GPS said you were. Then sometimes after starting it would be black again.

Ended up replacing the complete NAV Radio and having it reloaded at the dealer. The new ones come Blank and must be reloaded according to VIN and type.
So what I learned is..pull the radio fuse before connecting or disconnecting the battery. It messes with the NAV Radio when there is a voltage spike. This is just what I found thru experience.

 

Yep, I think I just learned that the hard way. Honestly, it now forces me to upgrade the system though, which I have wanted to do anyway. I bought a kit that gives you a larger screen and it gives you a more modern radio with all the bells and whistles, including Apple CarPlay. Once I get it installed, I will try and upload some images and report back on how I like it.

 

Good Idea... Just remember not to fuse the NAV/Radio up until it is all wired in and ready to go. And insert the fuse sharply without causing an spikes. Just My $.02 Worth