Expert: Peter G. Lee - 7/28/2006

Question
I have a 1990 BMW 325i. I have a DXZ535 Clarion CD player installed. Recently it has been shorting out, especially when going over bumps in the road. I took it to the local car stereo shop. They took the deck out and said all the wiring was good. Basically they said I wouold have to buy a new stereo! I don't want to buy a new one, this one is only 3 years old. Any suggestions?

Answer
When you say, “shorting out” I assume you mean blowing a fuse, would this be on the permanent 12v (+30) line or the ignition (+15) line or in the fuse box, you didn't say.

What we would do in shop if nothing was initially obvious would be to put a similar set in on the same connections and see if the problem went away, if so it’s the head unit and we would be then look to remove the cover and check for any burning inside, loose components or boards.
If the problem persists then it’s a wiring fault and just a matter of tracing from the radio to the blown fuse along the guilty wire until the short is found. A fuse will NOT  blow if the short is between it and the power source, the short needs to be up-line from the fuse. So if the fuse that blew is inline and say 6” from the set then the fault lies in that 6” area or in the set.