i recently replaced my stock non-bose fd head unit with another since the display light in mine burned out. old one out, new one in and a second new one in and i can't get it to work. it lights up and tunes channels so no code issues and if i turn it all the way up, i can hear it very faintly out of the speakers. i just got back in from checking all the fuses and re-installing the first replacement again and everything is as described above. if anyone can help i would greatly appreciate it. i'm going on two months now with no sound at all.
thanks in advance,
andy

 

If you have the orignal stock bose stuff except the headunit, you need a wiring harness, you than need to splice two wires together, search its been discussed many times. If you get a proxy error while searching, the sort the threads by most views in the interior section and I am sure it is one of those.

 

i don't have the stock bose equip. my car is a '94 pep. came with the base head unit and no stuff in the back, just the two door, two rear and one dash speaker. the unit i have in there now is identical to my old one and doesn't say bose. i also have a unit that says bose on the cassette cover, but it doesn't work either.

 

hmmm do you have a wiring harness for the new system?

 

it's the stock harness in the stock stereo, so it just plugs right in. any other suggestions?

 

It is possible that the stock stereo has some sort of a protection circuit that cuts power if there is a short somewhere along the speaker wires. Naturally, the only way to find the point of the short is to trace the wires, but you don't need to check the whole thing, just basically at the doors, jambs, and inside the dash radio opening. This is a bit of a guess though, because these protection circuits usually cut output completely, and it would also be strange to have a short suddenly appear when swapping a deck. Since you are simply doing an identical deck swap, nothing should have been tweaked hard enough for that.

You can try a third new unit, sometimes bad decks come in pairs, or you can get a new radio and harness, wire it up, and try that.

 

Does the car have a relay for the stereo in the fuse/relay box up front near the intercooler? If so is it intact?

How about sourcing a new power line temporarily just to check the source powers? (should be two)

 

no relay near the intercooler, never has been. i have tried a third deck to no avail. the unit is getting power because it keeps time, turns on and off, works the antenna, stores channels when the car is off, etc. it almost sounds like when i have screwed up grounding an amp in the past in other cars. i can hear the station broadcasting very faintly when it's turned all the way up, but it never actually makes regular volume.

 

Yeah I think Ive heard that sound myself from stereos - line level with like .001 watts..

Since the headunits are getting power probably easy to rule them out - amp power or ground would be my next bet, then speaker hookups - but I refuse to believe they all go bad at once

I tried to fix the stock stuff one time.. for about 2 hours.. then ripped it out and upgraded

 

If all your wiring to speakers is intact, then the next thing I would think about is that your stereo is actually a bose system. In this case you have to check your connections and fuses for the amp, and if everything is good, then try using a bose-ready deck. If three standard replacement decks don't work properly but your old one still does, then that adds even more to that being the case. One way to test for this is by (while the car is off) finding the wires to any one speaker, stick a wire in each hole at the radio harness (or better yet, go buy an aftermarket adaptor harness and use the free wires off that), careful not to touch any other leads, and then touch the connections of a 9-volt battery to the wires. If the desired speaker makes a pop, then there is most likely no amp and typically no short. A better option is to go down to the local stereo shop and ask if you can use an installer's tone generator, which will send a tone to your speaker. If you have no tone/pop in all of the speakers, then you have an outboard amp.

I personally prefer BicuspiD's approach: rip all the stock junk out and put a real stereo in there. Things have advanced in every way in the past ten years.