Car Stereos: getting wierd amplifier voltage readings, voltage readings, negative terminal

Question
Hi, I recently burnt up the main fuse going to my amplifiers. When trying to find out why I noticed I was getting 10v dc from the positive wire coming from my amplifier, when it was unhooked from the battery! I unhooked all wires going to the amp one by one checking the positive terminal of my amp each time and still getting a 10v reading.Finally I unhooked the ground and the reading went away. So I checked the ground wire by itself and got nothing, no reading what so ever. It is a good ground right to the body and shows no voltage and perfect continuity. I hooked it back up to my amp, just the ground wire and nothing else mind you, and checked the positive terminal of the amp and its there again, the 10v. Please help me I have tried everything and am usually very good at this kind of stuff. Oh by the way I tried two different amps and get the same reading with both.

Answer
Joe, It does sound like you are being very thorough.  That just makes it more frustrating, I know.  Is any part of the amp touching metal from the car?  If not, hook up the ground wire to the amp again.  Check the positive terminal, it should say 10v.  If so, go directly to the negative terminal and check.  If the amp is totally isolated from the metal of the car, you should get a 10v reading on the negative terminal.  If you do not get a 10v reading at the negative, while the positive has a 10v reading, there must be some sort of outside interference.  I would guess you have one of two problems.  Either your amps body is touching the power terminal or is grounded to the body of the car.  Or, there is a short somewhere else in the car, and the shortest route back to the battery is through your amp.  Shorts coming from the car are very hard to find.  Hope this helps, Scott