"Room" fuse keeps blowing and radio does not work

[L2RTSiAWD]

On saturday I got in the car and fired it up and put my face on the radio. No power, ok so maybe it's a fuse. I check and the radio fuse is fine but the "room" fuse is blown. I go to put another 10-amp and it blows the instant the fuse touches the connector. When I searched some people had said the room fuse blown will cause the radio not to work, however, I can't find why the fuse keeps blowing. Any suggestions there would be greatly appreciated.

 

[ddavisaf]

FYI: We figured out the room fuse mystery on my friends car. His alternator has a short, causing it to drain his battery and blow the room fuse. Everytime we put a new fuse in and started the car it would blow. So we finally sat out there two nights in a row for about 3 hours a day pull fuses/relays, disconnecting various electrical connectors, then tracing wiring. His alternator was a week old.

Check it out.

 

[L2RTSiAWD]

How did you finally detemine the alternator had a short? How did you test it?

 

[ddavisaf]

Ran a circuit tester in line with the positive battery terminal and the positive battery cable. We then watched for the light to dim when we unplugged various connectors. We kept skipping the alternator because it was just replaced a week ago. Finally we go the sockets out and when we unbolted the alternator connectors, the light went off. Took it off, tested it at Checkers and it failed three times in a row. New alternator, ran the test again and havn't had a problem yet.

 

[L2RTSiAWD]

Well I will keep that in mind, since I"m not ready to take the alternator off just yet.

 

[L2RTSiAWD]

Well I finally worked on it yesterday and I got it fixed. For me it was just a bad ground somewhere. I couldn't be specific only because I must have have pulled out so much wire from whoever owened the car berfore me, capped and electrical taped shit, that I don't know which of the 10 or wires I fixed was the problem. There is still a giant ball of wire from the old aftermarket alarm I have to go through one of these days.