Hey all. So for some reason, the pioneer head unit I just installed works great with a CD, but when I switch it to radio, there is no sound (not even static) coming from the left speakers (front and rear). I pulled the antenae wire out of the head unit, and turned it up to hear the static coming from only the right speakers. The unit was mildly used but worked fine when my brother removed it from his car a few months ago. Any ideas?

Check the balance and fade. On some stereo's these are seperate settings for each source. Meaning if you set the bass, treble, fade and balance for the radio, when you switch over to the CD, You can have different settings and they won't affect the radio settings. Maybe the balance was set to the right for the radio?

Since the CD is working, then the stereo's internal amp is good and the speakers are wired correctly.

Thanks for the suggestion, but I checked the fade and balance and all is good. Even with the balance all the way to the left speakers, there's still not even a hum from the left.

Does anyone know anything about antenna design? I'm wondering if the signal is broadcast in stereo (right and left), maybe my head unit isn't picking up or transferring the left signal? Does that make any sense to anyone?

[This message has been edited by Doc- (edited 09-13-2007).]

Mine did the same thing, I sent it back to Pioneer, they said it was a loose wire inside the headunit.

Check your wireing again,if it worked befor then something is wired wrong.There are a few diffrent ways to wire the fader and balance (realley the wrong way).When you have music playing and try adjusting the fader and balance is the music going to the speakers like it's supposed to (right,left),if not then you may have the fader\balance reverse wired.Make sure your antenna didn't come out of the radio.

It has to be a problem with your unit. Since it was working fine before you installed it, something has clearly gone amiss between then and now.
I have seen marginal solder joints fail upon minor impact. Silly as it sounds, you might try tapping it with the back of a screwdriver while is on ant set to radio and panned to that side. If you hear anything from that side you may be able to fix it.
I have been successful occasionally by hooking the device up on the bench with power and speakers. Then you open it up and tap all around with a pencil listening to the speakers for any signal on that side. When you find the guilty solder joint you just touch it long enough with your soldering iron to melt the solder and/or add a little fresh solder if it appears to need it.