Stereo Sound and warning sounds doesn't work when outside temp is hot

Sorry. This is going to be a dealer-only repair. Since 1994 GM has refused to sell us radio service manuals or parts so you are stuck with their two grossly overpriced repair centers. To prevent people from replacing their high failure rate cd players with aftermarket products, they began building the Body Computer into the radios so you have to keep them in the vehicle. Non of that benefits the owners but it sure makes GM a lot of money after the sale.

The dealer's service department also has entire books on diagnosing their audio and body control systems. I hope you get lucky and they find some other cause besides the radio, but the good news is with such a new vehicle, the problem should be covered under warranty, ... This time.

I would be willing to bet this will be taken care of under warranty, even if it takes until the vehicle is out-of-warranty. At the very nice family-owned Chrysler dealership I worked at, as long as an intermittent problem was documented while the vehicle was in warranty, it would be handled well into the future. "Documented" simply means they wrote up a repair order in their service department. I would be willing to bet GM has a similar policy although any dealership can try to change the rules if you aren't an informed owner. I can give you more details if necessary, but it probably won't come to that.

Intermittent problems are a major frustration for mechanics because if they do anything at all, and the problem goes away, there is no sure way to know it's fixed. All they can know is if it acts up again, it's not fixed. You can have the most conscientious and reputable people working on it, and trying their hardest, and customers will still get angry with them when they can't solve it right away.

check to make sure your grounds are good the one on the left end of dash look like it might be the culprit. also under the passenger seat. looks like all of them connect there.

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