Question on Boxster 911 Engine Swap

Hi Everybody. I have a MY2000 986 Boxster 'S'. I installed a MY2004 996 3.6l engine into the Boxster 'S'. I also installed the Motronic ME 7.8 ECU. I also installed the 996 Carrera Instrument Cluster which includes the Battery charging rate gauge and an Oil pressure gauge. The car runs like a dream and has plenty power/torque. My only problem is that I cannot get the A/C to work. The A/C relay wire White/Green on the 7.2 Motronic is on Plug II Pin 18. This was moved to Plug D Pin 27 on the 7.8 Motronic. No problem.
There is however a wire White/Red coming from the Boxster's M573 Climatronic Control Unit. This is the A/C Demand wire that goes to Plug IV Pin 6 on the Motronic 7.2
I cannot find the equivalent 'A/C Demand' Plug/Pin on the Motronic 7.8 or on the 996 Carrera's Climatronic Control Unit by the way, it's also a M573 Control Unit. Any help would be most welcome. It's hot in South Africa this time of year! Wayne, your books are fantastic, thank you! Regards, Eugene Dittberner

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[Casey at Pelican Parts]

I seem to remember this issue on a customer car, and I believe the A/C request is sent via CAN between the DME and Climatronic on the 7.8 cars. As I am sure you realized the DME needs to see the request from the Climatronic control unit. White/red is usually a switched B+ signal. Could you verify that the RED/White wire has solid B+ 12v when snowflake active?

- Casey