Audio Systems: 1995 Blazer Delco radio, plastic storage bin, delco radio

Question
Hello Parke,

I have a 1995 Blazer with a Delco radio/single cd player that loses power, (very briefly) every 5 or 6 minutes.     It happens very fast, like a CD skip. At first I thought it was the CD player but I find that it does the same thing with the radio. I made sure the fuse was making good contact but the problem remains, Can you point me in the right direction?

Thanks Parke

Answer
Hi Lou,

 This must be incredibly frustrating.   

This could be one fo two things - a bad unit or a bad power system.  If it's a bad unit you can just upgrade to something newer, but if it's bad power then you'd have just wasted good money on something that didn't fix the problem.

If you have more time than money I might suggest two things:

1) Bench-test the headunit-
if you have a spare battery or (much safer) a spare 12V power supply (the ones off an old computer would work great) you might just want to pull the unit out, power it up in a test environment, and see if the problem persists.
If so - you either have a bad systems board or some internal contact has coroded or worn out.
(BE CAREFUL WHEN USING BATTERIES IN THIS WAY - they can be very dangerous - I suggest using a large plastic storage bin with a lid and putting the battery inside of that.  That way you'll be safe if it leaks or explodes.)

2) Electrical System test:
The other test would be to pull out the unit and test the power cable (usually yellow).  Go to WalMart or RadioShack and get yourself a cheap volt-meter.  Hook it up to power and ground (check your manula or go online to find out the pin-out assignments on your make/model/year of car) and monitor it for ten minutes.  If you see the power drop below 11.5 volts then it's the car.  
There is also an in-line tube fuse on this power cable - did you check that?  
Is there also a (usually red) "pilot power" cable that turns the radio on/off by sending a voltage (usually 5 or 12V).  Is that cutting out?

Is there anything else on the same circuit (usually the cigarette lighter, dashboard back-lights, and/or dome/map lights) that is also behaving oddly?  Or are you constantly using any of these other things?  
Try, for instance, finding the dimmer control for the Dash backlights and turning them way down/off.  Does the problem stop?

Let me know if you get stuck or find anything suspicious, you and I can work it out from there.