Radio/Speaker noise

[Guest imported_blazer1997]

If anyone has any suggestions appreciate it. 1989 Reatta factory radio system had no problems but suddendly speakers have a deep rumble. Sounds like popcorn in a microwave popping.

Checked the antenna connection. Pulled it apart, and repluged it still there.

accelerating the engine in park the sound stays the same.

Depressing the brake pedal hear a one pop.

Also checked with the engine off and the key in the accessory mode ALL speakers are still distorted.

The sound stays the same when using AM or FM or cassette.

In older cars if the proble was ignation relataed hear it when the rpm increased.

Also looking for service manual 1989 Reatta used if poss.

[padgett]

Just fixed my 88 - replaced the radio module. Apparently the general bought a horde of poor capacitors (six around the output circuit) that fail and you get static on everything.

I plan to replace my originals (will find posts, might search on "capacitor") put you have to be experienced in repair of circuit boards.

[Mac Elliott]

I had similar problem with the right channel in my '91. After replacing the speaker, we eventually determined the source was within the amplifier section of the radio, which was repaired by Delphi. I don't recall the cost, but it was quite reasonable.

[sahein]

To determine if the the noise is generated by the speakers or the internally by the amplifier, on the 88 -89 you can mute the radio by pushing the up and down volume soft keys simultaniously. If the scratching, poping noise is still present while muted, the problem is probably the six capacitors located under the heat sink in the radio module. If the distortion only exists when not muted, The foam on the speakers edges probably deteriorated. The greatest probabibility is that both failure conditions exist and you need to repair or replace the radio module and replace the speakers. I recomend using oem speakers.