PCM2.1

[monster1]

The rear of my PCM2.1 has two antenna connection points - a black one and a yellow one.

 

I think the black one is for the fm radio antenna?

 

The yellow one I am not sure, I  have searched here and seen it described as either 'gps' or 'Diversity' input  - I don't think it is gps as I believe the GPS antenna is connected directly into the GPS module in the trunk.

 

Can anyone confirm what these two antenna connection points are for?

 

 

 

 

[Loren]

Exact model and year of your car please?

[monster1]

Hi Loren, its a 2005 Carrera S Coupe!

 

thanks

[monster1]

Gen1 997

[Loren]

It should be labeled "G1".

[monster1]

It should be labeled "G1".

The yellow port? - it doesn't seem to have any labelling next to it!

[Loren]

Yes yellow - but I think your car has the diversity antenna (amp) which is between the PCM and the antenna. Is this a repair or what are you trying to do?

[monster1]

Hi Loren, I'm attempting to take the PCM2.1 out and fit a PCM 2.0 in its place.

 

I am just trying to understand all the connections. The PCM3.0 has a yellow antenna point on the rear but its a different type of plug, and I believe it is used when the later car (Gen2) is specced with usb aux and iPod kit in the centre console!

 

Do you know anyone who has managed to retrofit a PCM3 into an earlier car?

[Loren]

 

 

Hi Loren, I'm attempting to take the PCM2.1 out and fit a PCM 2.0 in its place.

 

Do you mean replace PCM 2.1 with PCM 3.0?

I see to remember someone doing that... perhaps it was in a Cayenne.

[Mijostyn]

Monster 1, Did you buy this unit yet?

[monster1]

 

 

 

Hi Loren, I'm attempting to take the PCM2.1 out and fit a PCM 2.0 in its place.

 

Do you mean replace PCM 2.1 with PCM 3.0?

I see to remember someone doing that... perhaps it was in a Cayenne.

 

Yes,  oops sorry for typing error - I plan to try and change my PCM2.1 for PCM3.0.

 

Yes there is a chap I believe who has done this in a Cayenne in Russia.

 

I dont think its the most straightforward of retrofits!

[monster1]

Monster 1, Did you buy this unit yet?

Hi there - yes I have the PCM3.0 I purchased one off eBay - not proved it works yet - or proved I can successfully fit it either!

[Mijostyn]

OK, If I might, how much did you pay for it? Certainly you will be able to get music out of it and radio if you can integrate it with the car's antenna which I am not sure if they changed between versions. It will certainly fit physically into the dash. Some functions may not work or may require programming. The various units in the car talk to each other over the MOST bus, particularly the instrument cluster and the PCM along with the gateway module which then gets data from yet other modules. But, not to fret. If you can not get it to work to your satisfaction you have quite a few other options in the aftermarket. I totally re did the front end in my 06 C4S and it is fully up to modern spec.

Edited January 17, 2015 by Mijostyn

[monster1]

Hi Mijostyn, thanks for the info, yes I am aware about the coding issue - I will attempt to cross that bridge if and when I get there! I think the radio antenna is the same between models, although I haven't checked on the PET

 

Regarding the MOST bus, I didnt think the instrument cluster took a fibre optic feed - are you sure it does?

[Loren]

You may be confusing CAN with MOST.

MOST is for audio and navigation systems communication. MOST is on fiber optic cables.

CAN is for operation controls modules to communicate. CAN is on conventional wires.

 

The wiring diagrams from Porsche show various MOST configurations (depending on options).

[monster1]

You may be confusing CAN with MOST.

MOST is for audio and navigation systems communication. MOST is on fiber optic cables.

CAN is for operation controls modules to communicate. CAN is on conventional wires.

 

The wiring diagrams from Porsche show various MOST configurations (depending on options).

Yes this is how I understood it to be, which is why I was a little confused with the last suggestion that the PCM talked to the instrument cluster through the MOST system. It had me scanning the drawings though just to make sure!

[Mijostyn]

It does. A good example is the trip data. My PCM died and took the instrument cluster, the gateway module and the PASM computer with it. They are all interconnected somehow. I suspect the gateway module gets and gives information to and from both the CAN bus and the MOST bus.