FM does not work am does
 

Hey how's it going people who are hopefully a lot smarter than me I have a 99 Chevy blazer 2 door it has a stock radio in it the FM does not work just static but am works just fine one of the previous owners was springville city in Utah and they had installed a cab radio and someone told me they might have somehow disabled the FM part of the radio because it interferes with the cb I personally don't think there is any truth to that but could be wrong just wondered 1. Is it even possible to disable just the FM and 2. Has anyone else had this issue does anybody know something I could try to resolve the issue thanks in advance

Sean

I've never heard of such a thing but with the right information, schematics and instructions anything is possible. I've done a quick search on the internet and not found any information directly regarding disabling an FM radio for CB use and I doubt that's what's happened. It just sounds to me like the FM tuner took a crap in the stock unit and it's a terrific opportunity to replace it with a much nicer aftermarket unit.

I had a similar problem with my first s10. The reason behind mine was that some how the antennas are capable of being faulty. I spoke with numerous people that had the same issue. I just installed an after market deck and never used the radio. I eventually did replace it though as it wasn't very difficult to do.

sounds like an antenna problem, the physics between am and fm are different,

I have seen some CB setups that use an adapter to tie directly into the factory radio antenna rather than having a dedicated CB antenna. This shouldn't cause any issues with the FM radio (it doesn't in my brother's truck) but it might be possible. Just unplug the CB radio antenna connection to test it. If the FM comes back with the CB unplugged then the CB is somehow causing interference.

It is much more likely that the problem is in the antenna cable itself. Over time they can build up corrosion in the connections, especially inside the fender and engine compartment. In my experience FM channels are much more affected than AM channels, which is quite normal. You can pick up AM radio stations MUCH farther away from the transmitter than you can from an FM station. You should be able to replace the antenna and cable assembly with a bit of work, but if you do I'd recommend replacing the entire antenna and cable all the way to the radio. It's a bit of work, but that's the best solution. You can get a replacement that's the same style and mount, or you can go for the generic universal rubber ones. The universal ones usually work just as good as the factory ones, they just don't look quite as nice. If you decide to replace it yourself just Youtube car antenna replacement to get an idea of what is involved.

Dirty antenna?
 

I have a 1997 Jimmy, and I got like 5 or 6 am stations, and only like 2 or 3 FM stations, and it was pretty much just 2 church stations and 1 country station...

I even got an expensive car was, and then even the 3 or 4 stations I was getting, kinda got staticky...

I opened the hood, and sprayed some wd40 where the antenna is attached, and above the hood area , and sprayed the entire antenna, wiped and rubbed it, I got some rust, and paint, and lots of dirt off of it, even after a car wash...

Then i used some (gunk brand) glass cleaner spray on both sides where it attaches and the entire antenna, wiped it down again, and then wiped it down with plain water...

Then all the sudden I had like almost 18 to 22 FM stations that came in like crystal clear.

That's good advice, but after five years, hopefully OP has fixed the situation

broken cable connecting the antenna to the main printed circuit board (PCB)
 

At my cheap old international HPSS radio the problem was the broken cable connecting the antenna to the main printed circuit board (PCB) !!!