tips from corvetteradios.com
Information on Bad Bose Speaker Amplifier
(Squealing & popping) This is a common problem on Bose amplifiers produced by from a date 1985-1996 in Corvette, Camaro, Buick, and Cadillac, also any other car manufacturers that used the Bose system.
All of the green capacitors on the amplifier board were very low quality, and heat causes them to leak and go out faster. It is extremely hard to change the green capacitors if you don't have a electronic background or the equipment to replace these capactors, you need to have a experience electronics shops to replace the small green capactors, they are temperature values rating changes, the values are 1uf, 4.7uf, 10uf, 47uf Some cars with 2.2uf, 22uf this may change, depend on the type of board you have.
CDM box or Bose amplifiers/ Speakers?
If you have snapping and popping from some of the speakers, the CDM box can be Bad also if item was wet or water damage, to check for bad speakers. you can switch the right to left & left to right, if the problem changes, you have a bad speaker, do the same with the speaker amplifier, only do this if you have bad sound on one side (front are rear)
The CDM Amplifier
When the head unit is turned on and off, you should hear a click from the relay inside the CDM box can be found under the dash board and for Conv, in back of the passenger seat, water and corrosion can damage these unit CDM amplifier, check your windows
weather-stripping for leaks.
Did you know
1# If you hear a pop or static when you turn the stereo off, you may have a bad speaker relay.
2# If you have one bad speaker amplifier, you should have the two replace or repaired at the same time, the output from the amplifier decreases with the age of the amplifier.
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