I have a 2003 GT convertible with the Mach 460 system. It appears to all be factory stock and original with no modifications. I bought the car 2 years ago, had an intermittent loud hum in the stereo that would cause us to have to shut the radio off when it happened. I once tried unplugging the driver's side amp while it was making the loud hum and it immediately went away, only to come back later. Just recently, the loud hum stopped happening intermittently, and we now have no bass. I know there are 2 amps behind the rear seat. Does one or the other control the bass?
I read a similar post recently where the person showed pictures of his wiring that had apparently been altered. Mine appears original and unaltered. Would like to know if anyone has had a similar problem, or can explain what the amps control. Thanks so much!

 

It should be the same as my 96. The amps in the rear are for the bass in the front and rear mid/woofers (5x7) speakers. The front amp is for the frt/rr tweeters.

 

one amp is for the front woofers, one is for the rear. First start simple and check your fuses. Don't bother with the manual just go and pull/check each one, takes less time and you can then be sure its not a fuse. Don't forget the ones by the batt.

If they are good then at the least you have a bad amp, possibly a bad deck as well.

 

Check this out
http://www.carstereohelp.com/fordMach460.htm

I have been without the subs for a week now, this was the problem for me but instead of being unplugged the power wire was corroded so badly that it fell out of the connector

 

I have a similar issue.... Checked all above my subs and mach system have played nicely for three years. But driving down the road one ****ty day they went out. All connections are good fuses all god and pulled side panel with a glimmer of hope only find a perfectly good wire connected....any ideas?

 

the past two year really I have been hearing more and more of issues of the amps going out and that is what I would lean to with out having actually put a finger on the car.