Audio Systems: CAR RADIO SHUTS OFF, signal 12, repair job

Question
HI Peter
Thanks for such a prompt reply, I should have said the radio doesn't actually blow any fuses, it just doesn't come on.  When you remove/replace the same fuse it works again for a while and then goes off again.
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-----Question-----
Hi
I recently fitted a cd player into my wife's hyundai (can't recall the make at present).  Everything went okay,stereo worked for a while then on turning the ignition on, nothing.  If you remove and then refit the fuse in the back it works again for a little while and will then go off again. I have replaced the fuse with a brand new one and it still does it.
Can you give me any pointers that could cause this problem

Any help you can give would be appreciated.
Thanks
Andy
-----Answer-----
Hi Andy, weird one this, if a fuse blows then there is a problem between the fuse and ground via the unit, in this case, a radio. This would indicate a problem with the radio or a short on one of  the out puts from the radio such as  the antenna signal 12 feed, or maybe a positive speaker wire trapped and earthed out. The bad scenario is that there is an internal fault in the radio requiring repair or replacement.
Peter

Answer
Hi Andrew,
Sounds like there is a short on a speaker wire or the command signal lead to the antennae or amp and it is tripping out the overload safety in the radio. unplug everything apart from the three leads needed to work the radio, poss, acc & ground and see if it still does it, if so it's a bin or repair job, if not then you will have to check all the disconnected wires for a short to ground.
Peter