Here you go....

Here is a link that might be useful: Car radio repair in Austin

Problems developed with the radios on both of my trucks, different makes. Most of those repair shops are now gone in my area, too. So I bought for one truck on eBay, $50 delivered, and from local wrecking yard for $35 for the other. Both of those are working perfectly. I kept the originals for possible future repair or exchange if necessary.

I'm going to replace all 4 speakers. The 3 dead speakers have no resistance. I think our Hot Texas Sun is the culprit. When the new speakers arrive, I can take the old ones out and see what failed.

You are likely right about the speakers being mechanically shot but there still may be a radio problem as well. Back in the days when the car was in its youth, fairly common failure items were the power transistors screwed to the back of the radio chassis which were used to drive the speakers. If the problem remains after new speakers are installed, those two or four items would be another good area to substitute with new or known to be good used items.

I replaced all 4 speakers. Rear spks were easy to find, but the 2 front were not. The dash spks had to have a 2.375" diameter magnet to fit in the spkr tray. Asked on a Caddy forum and lucked out when a member supplied the brand and model number needed.
Back in business with 4 working speakers.

After this winter's snow and ice storms the radio stopped working. If the volume does come on only one speaker at a time or none of the speakers work.. Any ideas what happened to a radio that was working fine.

Dodge Neon 2001 sedan.

1st thing to do is, suspect the speakers. Use a tester to check continuity/resistance between the two speaker wires at each speaker. I too first thought the problem was in the radio. It was never the radio.
Once the speakers prove to have continuity/resistance, then check the connections at the back of the unit. Maybe something is loose/corroded making a poor electrical connection. Once those steps are taken and the problems still exist.....suspect internal radio problem.