I recently installed the Pioneer DEH-P400UB Headunit and was able to get the unit to turn on. For some reason I am not able to get any sound out of the speakers. I reinstalled the factory unit and the sound works fine. Now, I didn't get the antenna adapter because I didn't ever use the radio with the factory unit and figured no need for this one. One member suggested that I need to use the blue wire and route to the amp.

My stock system was the Bose 6 speaker w/ factory amp

Any ideas..........

Where did you ground the deck to?

I'm pretty sure grounding his deck isn't the problem. I think his problem has to do with he has to connect the headunit to his sub with the blue remote wire. Because without this I'm pretty sure (I could be wrong) that his amp wouldn't turn on to give power to his speakers.

you should just have to find a 12v switched signal and tap into the turn on wire at the factory amp. I dont know how this works with these radios. Crunkfunk might have a better explanation but this always happens when people add an aftermarket headunit to a factory bose system. I hope I didnt just repeat what the two of you already touched on Lol! Its late and I just wanted to chime in and try to help out if at all possible. I will check back with you tomorrow

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Well, that could be a problem I didn't connect the blue wire at all....

It would help to know what year and model we are talking about.

hes got a 2000 ssei

2000 ssei

make sure the speaker wires are connected properly, when i was installing my Pioneer deck i got 2 brown wires mixed up (speaker wires) causing no sound, randomly swapped the wires over and bam! works