2003+ CDR-23

I've got a GT3 coming with just the CDR-23, no Bose or DSP. I understand this unit uses the MOST bus communication system but I can't figure out what it communicates with, since there is no external amp or 6 CD player. I'd like to replace the CDR-23 with a TrafficPro but in looking at the back of the TP for connectors to the speakers, etc., they are all DIN/ISO or 8 wire-socket type connectors. Has anyone pulled a CDR-23 and looked at the back? What kind of connections does it use for the speakers? I'm assuming that it's not fiber but regular speaker wiring but I'd like to confirm before I order a TP. Is there any kind of online manual or wiring guide for the CDR-23 that any one is aware of? I looked at the Becker site but couldn't find anything. Karl

oh man no bose and most bus? That is not going to sound good. I hope you don't ever listen to the stereo- I have a pic of the radio on my site. The back actually looks very very simular to a cdr220 but there are two jacks in the back for the most bus that are different. The speaker connections are the same it seems though. The radio is easy enough to pull and since yours gets the code from the ecu it's not an issue other than radio presets. <a href="http://hobbystage.net/porsche/spr/" target="_blank">http://hobbystage.net/porsche/spr/</a>

Sean, Thanks. I looked at your site. Is the CDR-23 from a 2003 model? The connections on it look identical to those on the back of the Traffic Pro and I don't see any MOST bus fiber connections. I would have expected the C1-C3 sockets across the top to be fiber connections but in your picture they look like straight wire connectors. This makes me think it is from a pre-2003 car. Karl

yeah it is supposed to be. It is a picture of one that I was going to buy before I knew about it really. Hmm I dunno about what is what, but the weird black connector socket on the left with the two holes was the most hookup as far as I knew.

Yes, the weird black connector socket with two holes is the MOST connector. They are all standardized between various manufacturers (Amp/Tyco and Yazaki) If you power one up and look, one side will glow red (this is the transmit diode), and the other will not (this is the receive diode).

When the car get's here look as see how it is wired.... OR go to the dealer and look for a 2003 911 or Boxster without the BOSE not Hi-FI.... Pull the radio and LOOK!... I bet the speakers are run from it. NOTE: If you replace the CDR-23 unit with a Non-MOST unit you have to "hide" the CDR-23 unit behind the dash, keeping it powered and connected to the MOST BUS, just not to the sound system, or the alarm system will not be happy! WHy now wait for the Online Pro? It is to be on the C-GT so finally available in the USA.

I recently contacted Becker US about the Online Pro and they said there are no plans to make it available in the US. I've looked at the back connections for the OnlinePro and they are essentially the same as for the TrafficPro except for the GSM antenna hookup. There are no MOST connectors on the Becker version. But you raise a good point about the Carrera GT, assuming PCNA doesn't swap in some other unit. I don't really need the Internet and e-mail functions but I would like an integrated hands-free phone. I guess I don't understand the purpose of the MOST bus. It appears from Sean's picture that the CDR-23 has all the same wire connectors as the non-MOST units, including wire connectors for speakers, power, phone mute, and the CD changer. What in the world do they need a fiber connection for? Just to talk to the alarm system? I don't think the old units connected to the alarm system, did they? Karl

Karl, The story behind MOST is long and complicated. (I design MOST based DSP amplifiers for Porsche, Audi and Mercedes and even I have to wonder at times). In a nutshell, a single optical fiber can carry just about anything (audio, video, telephone). Currently MOST is about 25Mb/sec, MOST2 is going to double that. So, if you design a car with a fiber network, you can easily add DVD players, displays, just about anything you want and not have to greatly change the wiring harness and resulting EMC qualifications. If you did this with analog/copper wiring, you have to add LOTS of wire. As an example, think about your home surround sound system. In an analog/wire implementation you would have wires for left,right, center, rear left, rear right, subwoofer all coming from a processor and going to the amplifier (same in GM cars by the way). In an optical system (TOSLINK or digital coaxial) you have ONE connection that carries everybody at once. Much easier to build,install, cheaper! The German car makers have adopted MOST in this light and to standardize in vehicle entertainment devices (called infotainment devices). That means headunits, NAV, amplifiers, remote entry and alarm systems, CD changers, LCD displays, etc that are MOST capable can be interchanged with ease. MOST is for car manufacturers, NOT car owners. The assumption is once the car leaves the factory, no aftermarket devices will be needed. Now, Porsche was NEVER meant to be leading the MOST effort, they were going to follow Mercedes and Audi. As it turns out (even longer story), they ended up going into production first due to slips in cars being developed at Mercedes and Audi. The Porsche MOST systems are very very simple. Take a look at the new Audi A8L and you will see it has 2x-3x the number of MOST devices installed. (Which has kept my frequent flyer account full due to trips to Germany!) Unfortunatley, MOST is here to stay if you love German cars. As always, please feel free to email or PM me if you have further questions.

I will soon be traveling to take delivery of a 2003 996 with the CDR 23 with Bose. I've only seen photos of the vehicle. It's a two-day drive back home if I hurry and I'd like to know how to operate the sound system beforehand, no time to sit in the dealer's lot reading the owner's manual. >What is the TP button? >What function does SOUND control? >MENUE is presumably setup for clock, anything else? >What is the MAN button on the right? Finally, in the photo I see a cable poking out from under the radio which appears to be a female stereo mini plug connector. Any guesses what this would connect to? I have a Pono music player and a cable that would connect if that works. Thanks for any comments and info!