Radio mute by itself...

[kane67]

Ok, started to mute itself, frequency buttons not working when shows Mute.
Disconnected C21, tested buttons like manual says and they all work. So no sticking buttons.
Followed black/green to deck connector. Continuity C21 to deck connector (black/green) ok.

Black/green is ground from radio, right?
When I had C21 disconnected, it still remained Mute so it has to be internal something...
I removed radio and will start to check it soon.

Mute signal wire is black/blue so it kind of has a ground touch even c21 disconnected.
Could a missing ground confuse? All other functions work to lcd without any problems.

kane

[kane67]

Getting closer...

While testing covers off, I pushed this wire set towards IC board and mute went off.
Moving back and forth caused mute on/off. Next I need to get tube of thermal paste for IC’s.

Board connector looks very clean, soldering to board also good. I suspect wire/wires.
Testing continues tomorrow

[kane67]

I put fresh layers of thermal paste and soldering iron a bit to connector’s feet (IC board).
Seems to work perfect, I’ll update this topic if ”automute” returns...

[kane67]

Went for a ride today, about one hour. Kept radio singing
No Mute by itself, buttons Mute and frequency works perfect!

[Stew]

I had also taken my radio that far apart not long ago to manually eject a cassette, mine has also been working fine ever since. I think they sometimes just need to some of those internal connectors removed/replaced to freshen up the connections

[kane67]

Again mute returned by itself, took off radio and finally found the reason (I hope).

White wire was the cause, I don’t know its purpose/function but I replaced it and no mute anymore when I wiggle these wires.
Maybe somebody radioguru could tell what that wire function is in the system?

[RockportDave]

I unknowingly turned the CB on once and it over rode the radio. Pulled the shelter off and was checking the radio wiring when I noticed the CB on. Turned it off and radio started working normal.
Dave

[bellboy40]

That reminds me of one time I was riding with a buddy and he said his radio kept going off for a few seconds. He commented that that radio station must have a problem. Later he noticed that his CB was on but the volume was turned down. Every time the CB would receive a transmission it would mute the radio, but since the volume was turned down, nothing came out the speakers.
Sometimes it is the little simple things that get you.

[WingAdmin]

That reminds me of one time I was riding with a buddy and he said his radio kept going off for a few seconds. He commented that that radio station must have a problem. Later he noticed that his CB was on but the volume was turned down. Every time the CB would receive a transmission it would mute the radio, but since the volume was turned down, nothing came out the speakers.
Sometimes it is the little simple things that get you.

That has caught me out not once, but TWICE before. Both times I was sitting there trying to figure out what was wrong with my radio...

[kane67]

That would be a good thing to check if there is cb

In my case, non-cb wing.

[89 1500]

The board your have with the i.c.'s and caps is the amp/avc. I have a radio manual somewhere around here. Mine started the auto mute crap one day. I reached under and pushed up on my radio harness and mute went away. I removed individual pins from the connector and installed in new plastic problem remained. Pulled the radio and found damaged tracings in the boards behind the factory plug. I had to test with power to the radio sitting upside down and open that's when my hemo's fell on the little board and smoked it. I had a collection of radios with a few salvageable parts but not the little board I needed. Found an am/fm from an aspencade in a box and used the little board from the front of it. works good except for one thing the memory circuit is slightly different than that of a cassette radio and will not hold presets. Been searching for a parts radio for a couple of years I can't make myself give $75 to $125 for a parts radio that might have the part I need already bad. Also there were two Panasonic radio models which people will try to tell you are not interchangeable I think the older models are a G30P and can't remember the model in my friends 97. The newer being noticeably better to me anyway. I used the radio out of the 97 to troubleshoot my 89 when I bought it years back and did aux port installs, another simple upgrade if you can solder well and watch a video Sierra wants $124 plus round trip shipping for a 20 minute project. Good luck with yours they are pretty simple well after frying as many as I did lol.

[DenverWinger]

Did you ask Sierra if they have the little board you smoked?

[89 1500]

Na didn't bother. I look on ebay for radio deals daily. The one I messed up was a for salvage only sale I paid $60 shipped. All I had to do with it was swap the top from my damaged one and it was fine till I dropped the ball working on it. Another salvage deal will come along and I have time to wait it out. I'm going to do the 4x6 front speaker mod while the weather's bad. Amp install when it's too cold to ride.