Calling all audio techs!

CutNAction · 04-01-05, 08:01

Ok well about a year ago I bought a Pioneer MP3 player for my car (7600 model i believe). Well everything was going fine until one day I was driving down the street and all of a sudden it went out. The cd player is on and running but no sound is coming out. I started to drive back home and i hit a bump in the road, well then it came back on. So i knew what it was then. The power supply had to be loose. I got home and looked in the back, but that wasnt the case. The wires were all still intact. I checked the fuses in my fuse panel and they are all still good. What could be my problem...3 weeks without a radio really sucks!

Fritchard · 04-01-05, 08:53

is there a factory or aftermarket amp anywhere? sounds like an amp losing its ground or power somewhere.

CutNAction · 04-01-05, 08:56

Theres no aftermarket amp and I wouldnt think there is a factory one because its not the Monsoon system. It wouldnt be the fuse in the cd player would it because if the fuse was blown in the cd player the cd player wouldnt power on at all would it?

Fritchard · 04-01-05, 09:14

no, if the fuse was blown, it wouldnt work at all

this is a stock setup correct?

CutNAction · 04-01-05, 09:16

Everything is stock except for the cd player. One speaker going out wouldnt cause them all to go out correct? I dont want to rule out anything.

6']['9 · 04-01-05, 09:21

check the RCA's and all the speaker connections also check the wiring harness.

CutNAction · 04-01-05, 09:24

I checked the rear speaker connections (because as you know they are the easiest to get to), but i figured it couldnt be the speakers because if 1 speaker went out they all wouldnt go out correct? I would still be able to hear the other 3 and that would be way to crazy if all 4 went out at the same time!

Like i said when i hit a bump it came back on and when i hit another bump it went off so theres something loose and I have the slightest idea what the heck it is.

seracis · 04-01-05, 09:52

It sounds like there is a short in the signal lines. Most aftermarket head units shut down the output to all channels in the event of a short to one of the speakers. The easiest way to find it is pull the radio out enough to get to the wires. If the radio has sound, you need to do whatever it takes to get it to go quiet. With the radio on and no sound, take one of the speaker leads and cut it at the connection where the factory wires meet the head unit wires. Just cut one wire of the pair (white or white/black, grey or grey/black, etc.). If the radio starts making sound after you cut a wire, odds are that is the speaker that is shorting out.

Blazern00b · 04-01-05, 10:38

Easier way of testing for a short than cutting wires is to back-probe the wires that run to the speakers. Do this by un-plugging the head unit, and then taking a DMM set to continuity check. Connect black lead to chassis ground, and then probe the speaker wires, colors are white, gray, violet and green. Each has a primary color and a black stripe wire, which is the negative. If the meter shows continuity then that is the speaker shorting. Vehicles wiring is probably OK if it is OEM and you have not changed anything. Chances are its a broke terminal on the speaker itself, that is loose and shorting out.

If you have exhausted all efforts, take the unit and wiring harness out, and call around to the local stereo shops to see if they can bench test it for you. Some do it free, and some charge a small fee, usually 10-20 bucks. This will finallize the troubleshooting and let you know if it is internal to the deck.

Sometimes the Firebirds have OEM Delco amps. The best way to verify this is to see if the blue remote wire from the decks harness is connected to the blue wire on the aftermarket adapter harness, this of course is assuming that it was not hacked off and hard wired. Either way, the amp wire would have been wired up by someone to get sound if it had an amp. Next best thing is to use a tone generator and try and tone the speakers without any power to the vehicle. If you have tone come through, then non amplified. No tone till the blue wire is energized, then its amped.

Note: You can also substitute the DMM with an LED test light. Not sure as to where to buy them other than from a tool dealer. I get mine from Snap-On and Matco.

Recomended Tools:

http://buy1.snapon.com/catalog/item....re&dir=catalog

http://www.sears.com/sr/javasr/produ...26+Accessories

http://davidnavone.com/installation.html

DCopp · 04-02-05, 05:55

sounds like a loose OEM ground wire....

CutNAction · 04-02-05, 10:04

I knew I could always count on you guys!

I started to create a thread over at the Fbody forums, but due to the lack of electronic forum participation I thought the brilliant minds of Autopia would know the answer.

I just went outside and unplugged one of my rear speakers and sure enough its working now. So then I unplugged the other rear speaker and reinstalled the previous one and it worked. So i fiddled around with both of the connections for the rear speakers and the terminals on the speakers are crooked and loose. I really need to get me some more rear speakers.

Just wanted to thank you guys with such descriptive answers that helped me thoroughly.

Thanks again!!!

Blazern00b · 04-02-05, 10:18

Glad it was an easy fix. Broke terminals are probably the biggest problem i run into daily.