radio blowing fuse every time i plug it in

[Matt4545]

Well before i tore my engine down to do head gaskets, my main jumper fuse under the hood blew. i tore the engine down, rebuilt it, replaced that fuse and new battery and it ran fine. well the ROOM fuse under the hood also blew, and everytime i replace it, it instantly blows. so when i unplug the stock radio, and put the fuse in, it works untill i plug the radio back in. the second i plug the stock radio in, it blows.

oh and before the main jumper fuse blew, the radio worked

99 legacy gt limited

any ideas?

[AussieDan]

Well, something had to have caused the main fuse to blow. Have you figured out what the cause was? Whatever it was, something was passing 30+A in order to blow that main fuse.

It's possible that whatever caused the main fuse to blow also killed the radio, and now it has a dead short to ground internally.

The room fuse (fuse #25) feeds 12v to pin 6 on the radio plug, it's the blue/red wire.

I would check the resistance between pin 6 and ground (pin 11 - black) on the radio. If you see almost no resistance and then you've found your short.