Audio Systems: Radio install kills battery, filter capacitors, gmc sonoma

Question
I have a 98 GMC Sonoma, I installed a radio, and an amp into the truck, and now the battery will die after a three day period of non-use, I found that to stop the issue, I had to unplug the power from the amp to the battery. I've taken it in to were I've had the radio installed but they don't have a answer, but I don't think they tried to hard to find the issue. I've also taken it to others and again they don't seem interested in the problem. Seeing that it takes three days to see if the problem is resolved I don't blame them, and I can't leave my truck with someone that long, I've done everything I can think of but this is a three year old problem for me now. I just don't know how if the truck is turned off, the radio/amp is still drawing power? even though the radio says it's shutting off. Is there any troubleshooting that you can think of? Lately I've been thinking that it's the lead that goes into the fuse box from the amp, but I don't know what fuse it's supposed to go into. Thank you for your time

         Eric


Answer
Eric,
You may want to use a 12 volt test lamp and check to be sure that when the stereo is turned off the remote on lead from the stereo to the amp does NOT have any voltage on it. The remote wire should only go to 12 volts when the stereo is turned on!. I have seen defective filter capacitors that had internal leakage and when a vehicle sat for a few days the leaky caps would cause the vehicle battery to drain.

TOM,
T&D ELECTRONICS
tdeser@zoominternet.net