So when I got the car it had a pioneer head unit in it that didn't seem to function, so I got to work ripping the dash apart. Also in the back of the car was the factory delco unit. Both units sound like they power on and both will accept CDs, but no display shows up on either unit. The pioneer will actually play the cd but obviously I can't adjust the volume or anything. I'm thinking there is something wrong with the wiring harness somewhere??? Any thoughts?? I don't think either unit is broken because they are doing the exact same thing.

--Edit---

Posted in the wrong generation, whoops! This was meant for 4th gen, but maybe you guys can help anyway!

 

its just a coincidence that both are broken. theres no display wire, just 12V, memory, ground, and speakers.

 

So I guess I should find a known good head unit, plug it in and see if It works or i get the same problem???

 

Moved to 4th gen.

 

Yes, hook up a HU that is for sure in working condition and see if the problem persists. Let us know!