Expert: Cleggsan - 5/3/2011

Question
QUESTION: Good Morning, I have a 1999 Chevy Suburban with a ACDelco Radio, cassette and CD player. The speakers will shut off and come back on. This seam to happen more when it is cold. Usually speakers come on when I first start the car then as I drive the speaker will stop, they will usually come back on within 5 minutes. The problem seams to be getting worse. Your thoughts?

ANSWER: In the cool weather, like in Idaho, during about 6 months out of the year it is not uncommon for moisture to accumulate on the disc inside the cd player.  It takes some time for the moisture to dissipate and the discs to read clear.

If you are listening to CDs when this occurs it may be the cause.

Let me know under which conditions the drop out action occurs.  CD only (as bove), tape only, radio only or all of the above.  

If, for example, it happens under all conditions it may be the power amplifier going into protection mode.  This is most often caused by a short in speaker wiring or, in some cases, a shorted voice coil in one of the speakers of the automobile.

Let me know further.



---------- FOLLOW-UP ----------

QUESTION: I don't think it is a CD issue. I mostly listen to the radio. As a test I tried the CD after the radio sound went dead just to rule out it being a radio problem. Is there a fuse I should check on the voice coil. I'm not sure where the voice coil is?

Answer
It would not be a fuse since the sound comes back on.

If you are getting the drop out on any or all of the program modes then it is most likely an amp or speaker situation.

Also, check the ground wire of the head unit and the amp.  They must have a good ground.  Some times one must lift the ground wire, sand the metal part where the ground wire is attached, clean it up and screw it down again more tightly.

The voice coil is inside each speaker; it is what drives the cone in and out to reproduce the sound signal being fed to it by the amplifier.  If you know how to lift the speaker wires you should disconnect, at the amplifier, all speaker except for one.  Then listen to each one, one at a time, one by one. This can help you identify which speaker is causing the drop out.  Once that is known you can check the wiring more carefully and if necessary connect a VOM or ohmmeter to the speaker terminals to see what you are measuring, etc.

Let me know.