I just got a new radio for christmas for my 1999 F250. I hooked everything up properly, double checked, triple checked, and even more just to make sure I didn't short out the system. So I plugged in the radio, and went to play music to check if it was working, and it was only coming out of the driver side door, and very faintly out of the passenger door. Both rear speakers were out. I unplugged it, rechecked the wiring (again) and plugged my old stock radio back in. Same thing, driver side is good, passenger side bad, and rear two non existent (it's an extended cab by the way). I have no idea what I did wrong or what I should do to combat the issue. Did I fry a fuse, or did I wire everything wrong or are all the speakers blown and I had no idea? Any feedback would be helpful!!

 

I would temporarily switch the wiring so the front left output goes to the front right speaker and vice versa. If the sound still only comes out the front left, it's probably an issue with the speakers themselves.

You did check the balance/fader on the new radio to make sure it's centered, right? (Edit: Never mind. I see it has the same problem with the old radio.)

 

which radio did it come with. Some extended cab models did not have rear speakers. Is it an XL Model?
On vehicles equipped with the M100 ULC AM/FM radio, only front door speakers are used.

 

I tried both switching the wires and I tested the balance multiple times. I'm not sure what exactly else there would be too check left.

And yes, I have rear speakers. It's the XLT, although I'm not sure of the radio model. The rear speakers are the same as the passenger, little to no sound. So I'm just lost as to which direction to go about.

 

You are absolutely sure the wires are correct. Is the radio new? Put it on the bench and do a bench test with all the speaker wires to make sure the truck isnt the problem. Hook up the battery to the radio with some wire and go from there. You dont need a antenna just listen for the static.

 

Here is a PDF I put together for you. I think you have to download it to view it, but I'm not sure.
http://www.4shared.com/office/sIpLS-...250_Audio.html

 

So now for a few stupid questions:

1) Did all the speakers work with the old radio?
2) Did you use a conversion kit with the factory-adapter plugs to wire-in the new radio?
3) Do you own a true RMS DMM? (no, not a loaded question - but just a 'light-stick' won't help you for troubleshooting).