C5-Bose, electrical Guru's take a look...

[muncie21]

My original HU has been replaced with an Alpine unit. Overall I'm fairly happy except one annoying thing. My subs (in the doors) only work in the morning and late at night. I think it might be a grounding issue either with the Bose Signal Processor, or the amps in the doors. Any idea where these units get their ground from? Other suggestions, or ideas?

[bogus]

damn. that's super wierd. I know the C5 pros will come in shortly.

[muncie21]

The bad thing is that it's getting hotter here in NM. Pretty soon my subs will only work between 1am and 3am

[EatRice]

It would have to be an issue with heat. How to fix it is the real question. It would be internal somewhere. I am guessing the head unit is powering the speakers. And only the subs stop working...does the head unit power the other speakers as well? How did you wire the head unit to the subs.

What is odd is both subs do not work. That makes me think it is the head unit because what are the chances of two amps going bad at the same time? But it could also be the head unit...maybe it is not wired correctly or maybe it is bad. Hard to diagnose online.

[Nelson V.]

Originally Posted by muncie21

My original HU has been replaced with an Alpine unit. Overall I'm fairly happy except one annoying thing. My subs (in the doors) only work in the morning and late at night.

I think it might be a grounding issue either with the Bose Signal Processor, or the amps in the doors. Any idea where these units get their ground from? Other suggestions, or ideas?

Check this out:
http://forums.corvetteforum.com/show...m_id=20&arch=1
I don't remember if I ever heard back from this person (Slickman). So, I don't know what ever happened with the problem he was having (sounds very similar to yours). You may want to PM him for more details.


Nelson V.

[bogus]

personally, I would ditch the bose completely.

[muncie21]

Nelson, thanks for the link. After reading Slickmans post, it seems he had the same problem that I have. Regarding the wiring configuration, here's what I know; and it ain't all that much so don't get too excited.

The C5's have 3 plugs (actually 4, but two are connected together) that connect to the HU. One plug (c1 and c2) is the standard GM radio harness plug. It connects power, remote amp, power antenna, and the front/rear left/right speaker outputs. I have this plug wired to the HU just like you would normally wire in any aftermarket HU.

The two remaining plugs (c3 and c4) are specific to the C5 bose unit. The c3 plug is supposed to receive signal from the HU and send it to the Bose Signal Processor, which processes the signal and sends it back on the same plug. The signal is then supposed to go out via the C4 plug to the subs in the doors. The only thing I have connected here is the yellow (common, not ground) wire from the c3 plug to speaker common on c1/2. If this isn't done the subs won't fire at all, regardless of time

When my subs go out the rest of the speakers still work. This leads me to believe there's a common link between the pair of subs. All I can think of is the Bose Signal processor and power/ground. If the amps on the subs are connected to a common ground, losing that ground would make them both go out. Or, if the Signal processor uses a relay that doens't fire it could make the system go out. What I don't know is if the subs will fire if the Signal process is turned off.

I know it's a long rant, but I've been dealing with this issue for the last month + and have been getting nowhere. I'm almost ready to shove the system out the door and rewire everything.

[EatRice]

Muncie.......personally I would toss the rest of the Bose. You will have less head aches and better sound. I do agree with you though on the problem. Something that is common to both speakers is turning off somewhere. I forgot about the processor in my first post. That is most likely where your problem is. What I would do is test for power at the processor then test again when it is off. I would first try to find out of soemthing external of the processor is shutting it off. Do you know if the processor turns the amps on or does the HU? Could be the processor is truning the amps off.