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cdm location 1990

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Old Jun 22, 2009 | 11:36 PM
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Default cdm location 1990

I removed the lower hush panel off my dash and dont see anything that resembles this cdm. I see a bunch of spliced wires that may have gone to the cdm I am not sure.

I see a row of relays and on top of the can feel something up there but not sure if its just the inner dash frame I feel or what. is above these relays where the cdm should be? or does it sound like it was removed?
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Old Jun 23, 2009 | 05:05 AM
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Originally Posted by jeffp1167
I removed the lower hush panel off my dash and dont see anything that resembles this cdm. I see a bunch of spliced wires that may have gone to the cdm I am not sure.

I see a row of relays and on top of the can feel something up there but not sure if its just the inner dash frame I feel or what. is above these relays where the cdm should be? or does it sound like it was removed?
i take it you are on the passengers side - ??? "a bunch of spliced wires" is not a good sign! after you remove the hush panel, you will see a bunch of wiring harness connectors that are fastened to a metal plate/bracket - the cdm is mounted behind the metal plate. there should be 3, 4, or 5 (???) connectors plugging into it + the radio antenna. not sure if there are any relays in the vicinity - never took a mental note... if you have a FSM, all the info you need is there. finally, IT'S A BITCH GETTING THE THING OUT!!! hope this helps...
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Old Jun 23, 2009 | 08:31 AM
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I guess mine is probably gone then. I found this picture on ebay and don't see anything like this so far while looking up under the passenger side of the dash. I am not sure of the dimensions of this but it almost looks the size of a GM ecm so maybe I have to remove those relays and it will be up further into the dash closer to the glove box.




Last edited by jeffp1167; Jun 23, 2009 at 08:34 AM.
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Old Jun 23, 2009 | 12:14 PM
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IT'S A BITCH GETTING THE THING OUT!!!

Here! Here! I second that emotion. Damn near have to be a midget contortionist to wrestle that **** outta' there.
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Old Jun 23, 2009 | 12:24 PM
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Originally Posted by onedef92
IT'S A BITCH GETTING THE THING OUT!!!

Here! Here! I second that emotion. Damn near have to be a midget contortionist to wrestle that **** outta' there.
if thats the case then it has to be above those relays and out of sight because anything I can see would be easy to remove.

so maybe its still up there
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Old Jun 23, 2009 | 08:43 PM
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Jeff, you'll have to excuse my ignorance, but what is a CDM?
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Old Jun 23, 2009 | 08:50 PM
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This thing is about 8 inches long by about 5 inches wide.You need to be on your back looking up to see this POS.While on your back it is about 6 inches in front of your nose.This thing is buried.
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Old Jun 24, 2009 | 08:22 AM
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Originally Posted by gw962
Jeff, you'll have to excuse my ignorance, but what is a CDM?
it is the heart of the bose system so I need one badly but want to know for certain if mine might still be in the car.
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Old Jun 28, 2009 | 08:02 PM
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The CDM is the heart of either the stock Delco or the Bose system. THe Delco CDM has a finned heat sink at one end (for the internal power amp) where the Bose has a smooth piece of metal (since the power amps are in the speaker enclosures). Otherwise they look the same (other than different part numbers!).

If you have the hush panel off, open the passenger door, kneel on the ground, put you right ear on the door jamb where the hinge is, and look up under the dash. On that side of the CDM there are three connectors, blue, black, and white.

It is hard to remove and harder to install but can be done. Mine's been in and out about half a dozen times (don't ask).
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Old Jun 28, 2009 | 11:03 PM
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Originally Posted by rickso84
The CDM is the heart of either the stock Delco or the Bose system. THe Delco CDM has a finned heat sink at one end (for the internal power amp) where the Bose has a smooth piece of metal (since the power amps are in the speaker enclosures). Otherwise they look the same (other than different part numbers!).

If you have the hush panel off, open the passenger door, kneel on the ground, put you right ear on the door jamb where the hinge is, and look up under the dash. On that side of the CDM there are three connectors, blue, black, and white.

It is hard to remove and harder to install but can be done. Mine's been in and out about half a dozen times (don't ask).
OK I removed the hush panel and looked stright in below the fuse box and forward a little. there is a plastic panel that looks like it covered something and this cover bolted to something. I see the antenna wire and the other antenna wire that would go to the radio itself. both are not connected to anything.

also found this bundle of wires that have been hacked for some reason did these originally go to the CDM?

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Old Jun 29, 2009 | 01:55 AM
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Originally Posted by jeffp1167
OK I removed the hush panel and looked stright in below the fuse box and forward a little. there is a plastic panel that looks like it covered something and this cover bolted to something. I see the antenna wire and the other antenna wire that would go to the radio itself. both are not connected to anything.

also found this bundle of wires that have been hacked for some reason did these originally go to the CDM?

What a mess,I cant imagine trying straighten this out.
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Old Jun 29, 2009 | 05:07 AM
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yeah I'm about to abort mission ..... I will probably end up sending this c/d bose radio to doctor don have him go throufht it then just sell it.
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Old Jul 1, 2009 | 04:20 PM
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Sell which, the car or the CDM/radio it's built around?
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Old Jul 1, 2009 | 05:44 PM
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Originally Posted by Z51JEFF
What a mess,I cant imagine trying straighten this out.
Does any of this work it looks like speaker wires love the wire nuts..sigh.. how about a pic of the head unit if it works now if not my guess is aftermarket head unit pulled out and bose amps in speakers bypassed..
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Old Jul 1, 2009 | 05:48 PM
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Originally Posted by rickso84
Sell which, the car or the CDM/radio it's built around?
the radio
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Old Jul 1, 2009 | 05:51 PM
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Originally Posted by ddahlgren
Does any of this work it looks like speaker wires love the wire nuts..sigh.. how about a pic of the head unit if it works now if not my guess is aftermarket head unit pulled out and bose amps in speakers bypassed..
funny thing is though, previous owner never put different speakers in the car it more looks like they tried bypassing the cdm to get the system working almost.
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Old Jul 1, 2009 | 06:57 PM
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Originally Posted by jeffp1167
funny thing is though, previous owner never put different speakers in the car it more looks like they tried bypassing the cdm to get the system working almost.
If this is not a show car that needs points and something you want to drive and enjoy I will offer a bit of advice .. pull all the bose stuff out and replace it it is just not worth the effort unless a judged car. I have piles of Bose stuff claimed to be working but hitting on the combinatiopn that it all works is mind boggling. Worse yet once it works it might be for a very short time until the next part breaks. The best move I ever made was to resign myself to changing all and rewiring the car for new speakers. The reason being is the bose shares speaker ground and is un friendly to modern systems they will clip and distort trying this at low volume levels been there done that. I finally istalled a kenwood double din deck and alpine speakeres and paid around 475 for all the parts.. the result is it rocks and while not audiophile quality is is so over the top from what i had worth every penny. Your wiring is hacked so supect there is no going back so no sense trying..
Dave
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Old Jul 2, 2009 | 12:37 AM
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I went through all speaker amps and the CDM not expecting much,CD still doesnt work but this kicks some serious a$$,for early 90s technology it smokes and Ive put systems in cars in the past.
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Old Jul 2, 2009 | 07:58 AM
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I have a plan "B" don't worry. I just thought it would be nice to have the correct bose in the car is all. Heres plan "B" aside from it having a black face the buttons are grey and probably would go well with the other corvette dash parts. I never listen to c/d's cassettes, just mainly listen to one radio station and dont need a loud stereo in the car .... But here is plan"B" just getting it mounted is the only issue. The bose isn't as wide as it for one and there is a litlle difference in height, maybe a custom adapter plate would fix the issues.



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