Audio Systems: my aftermarket system has no speaker sound, ford f 150, rca cables

Question
Ok, my truck recently would not pass smog, my mechanic disconnected the battery, which my system is not hooked up to...it is hooked up to the ignition, so when i turn my car off and on my amp comes off and on...but now since the battery was disconnected i have no sound, not from my 2 12's nor from my door speakers.  Yet my stereo says im playing a cd...what is the problem...also my amp does not come on and it does not have a power button,
please help
monique

i own a 97 ford f-150 v8...automatic...

Answer
I gaurantee you that the amp and the stereo are indeed hoooked to the battery (even if it is key switched).

However, it is impossible to accurately determine the problem (via email) with the information given.
I do not know how the system is wired, but if all of the speakers get their power from external amps, it sounds like you may have a bad fuse for the amp(s). This would explain the CD working and yet you have no sound.
There are other possibilities but I would start by checking the fuses and the RCA cables.

Sincerely,
J Mael