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CDR23 radio wiring harness connectors

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I would like to remove the aftermarket Kenwood head unit and amp and reinstall the factory CDR23 and Bose amp on my 04 C4S, but the previous owner cut the radio connectors from the wiring harness. One of the reasons I want to do this is that whenever I scan the car with Durametric, I get a lot of red flags under PCM and the application crashes whenever I try to clear fault codes.

(I have uninstalled and reinstalled, no change. The same Durametric system works perfectly when I try the same process on my 01 C2 with correct radio.)


I've been trying to locate inexpensive replacement connectors, but have not had any luck. There seems to be one set on ebay, but the seller is asking double what I paid for the radio. Calls to wreckers yards have not yielded anything yet, they don't seem to be interested in selling such low value items.


Anyone able to locate a cheapish set of connectors? Its the kind of thing I hoped any car audio shop could sell me for $20 or so.

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Thanks Loren,
I have spliced the correct connects onto the harnesses, connected up the CDR23 and Bose amp and run a Durametic scan again. For the first time since I owned this car, I can clear all the fault codes and Durametric doesn't crash when it tries to clear the AC faults - green lights across the board :thumbup: .


I do have the following outstanding issues to address.

1. My CDR23 powers up but I get an error 'Protect'. Does the radio need to be coded to the car, and if so, can this be done with Durametric Pro, or only PIWIS/PST2?


2. I have located 2 ends of the amplifier end of the fiber cable, what should the second connector go to?

3. All the speaker wires on the old Bose amp connector have been cut and used to connect to the output of a replacement Alpine amp. I guess this means the Bose 2 ohm speakers have also been replaced with aftermarket? Is it better to retain the Alpine amp instead of replacing the speakers?

4. If I do retain the Alpine amp, will the CDR23 connect to the Alpine amp via the CDR23 speaker outputs, or have these been disabled so it drives only the fiber output? If disabled, is it possible to re-enable via Durametric or PIWIS?

5. If I go ahead and re-install Bose speakers, how many speakers are needed? Does the 04 C4S cabrio only have door speakers or others elsewhere?

Edited by SpawnyWhippet
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  • Admin

We are talking about a 2003 or newer 996 (with MOST fiber optics) right?


1. Yes, you will likely need a PST2 or PIWIS to code the radio and add the radio in the MOST setup.


2. That will depend on the other (MOST) options on your car. I have posted the diagrams here on the site (please search).


3. Ask others on that one.


4. CDR-23 Radio to amp connection requires the MOST fiber optic cable. So if you want to use the CDR-23 you will need either the BOSE amp or the Harmon amp. The output of the amp to the speakers is always a wired connection.


5. Again this will depend on your cars options - the BOSE amp supports 6 speaker and a sub-woofer.

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  • 8 months later...

Sorry for dragging out an old thread, but I am struggling to install the original CDR 23 BOSE system in my car.  Is there a way to test the amp to see if it is working?  The head unit powers up and seems to be working, but there is no sound.  If I understand correctly, the MOST cable is the only output from the head unit to the amp and that all the speakers are driven from the amp. All fuses appear to be good.  So I am thinking the next variable is the amp, but I don't know how to verify if the amp is serviceable or I should search for other faults.

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