Replacing PCM1 with aftermarket headunit and factory amp - no sound

Hi, I have posted on 911uk about this, but have not had any answers. I am stumped right now. I have a 2002 car with PCM1, a factory installed amp and cdc-3 cd changer. No Bose, no MOST. I have the black connector from the PCM1, and the yellow/green/blue connector (all of which is populated). It did also used to have a phone. There are also 2 locking connectors - blue and black, which I thought were for the navigation cd/dvd (which I've also removed) and the phone. I can power up the new headunit but I cannot get sound from it. I am using this harness - https://connects2.com/Product/ProductItem/CT20PO02 which one 'installer' has indicated is the correct one, yet the maker (Connects2) says there is no harness available at all for my car as the amp is on either the blue or black locking connector and not the yellow one, which based on the AliExpress PCCM (on 911uk and other places) thread and other posts, doesn't seem accurate to me but may very well be since I cannot make it work. If they are correct and the amp is actually on one of the locking (blue or black) connectors and not the yellow plug in the multi plug, which connector out of the 2 is it? I have reconnected the PCM1 and it does work and there is sound, so it isn't a car fault. I have bench tested the new headunit and I can get sound of it there as well, using the rear RCA connectors, therefore I know the new headunit definitely works. This appears to be a 'me' fault, not understanding how to wire this in. I have connected the antenna output from the headunit to the amp switched live as everything I have read indicates that is what you need to do to wake it up. Do I do away with the yellow to red connector and wire it in from the yellow connector manually? Is this - https://connects2.com/Product/ProductItem/CT53-PO01 what I should be using? Or do I need to rip out the old amplifier and replace it with something else? Pictures below. Yes, the antenna to amp power on is a bit jank, but is temporary to test, at the time of the pic I did not have any female bullet connectors to put on the wire (I do now). Thank you. Temporary jank to test, I did have it in a separate connector block for a bit. Antenna to switched live of the amp, I think? Aftermarket headunit wiring.

From searching the interwebs - this looks to be the pinout of the yellow, green and blue plugs: Is there a connection for the yellow pin 6 to the new harness? Something needs to turn the amp on. -Tom

Here is a link to the full pinout for the unit: https://www.pff.de/wcf/file-download/368366/ It looks like what is labelled as Plug II has pins 6 and 14 for the DSP(amplifier). So your amplifier may indeed not be getting power and ground. What is labelled as terminal 30 - is typically unswitched 12V - constant power. And Terminal 31 is normally ground. Here is what I think is your amplifier - showing terminals 30 and 31 and also pins 1 and 17 coming from the Plug II pings 5 and 14 for DSP (amplifier). Don't know if any of this helps. -Tom

Thank you! So, yes, I thought it was getting a switched live, as all information pointed to using the antenna wire (blue) from the headunit. That is also the white wire that goes into the black plug. Which is in the picture attached. I have tried various permutations of this, and nothing worked, until I realised the Orange wire in the black plug is for the ignition switch - switched live. Tested it, and bam, it works, sound. So orange needs to go to red/black on the Yellow connector (I have just merged the two wires together from the headunit side). It works, so I assume this is ultimately fine. I wonder if essentially the antenna wire in my headunit is not actually outputting power at all, although I had directly connected the white (pin 5) directly to pin 6 on Yellow and it didn't work.