I have a 2004 Ford F150. I have had it now for about 3 years. It has the factory stereo and recently we have lost sound to the speakers. The stereo still works just fine. We had a few weeks when we would start the car and the stereo would send sound to the speakers, then would not work for several starts, then would work again. Now, it seems to be fully lost. I've checked fuses and found nothing that helps. Is there something else I can check??

 

Loose wires maybe?

 

all of your speakers stopped working at the same time? sounds like the outputs are toast. if you can, take the deck out, take the pos/neg speaker wire out from behind the deck and touch it to a AA battery. the speaker should pop. if not then its your speakers. if it does then its the deck

 

I would check the wiring harness. If I remember right that has it own plug for speakers and the power stuff on its own plug. Did you ever smell burnt electrical smell? Does your door chime still work? on some it played on the speakers. Just throwing Ideas out there for you.

 

My 2004 F-150 did the exact same thing yesterday. I was on a 6 hour trip when it went out. It started after I had moved the front seat upward. Although moving the wires under the seat did not make a difference. Did you ever figure out what was causing the problem?