The 12v supply to the MS2 card is for the idle stepper motor control chip on the MS2 card. You should connect 12v to the proper location, as the MS2 docs say it keeps the stepper chip cooler. I did not connect it, the chip does stay cool so far, and its NOT needed to at least download the code, and run the engine. If you do connect 12v, you MUST disconnect it if you put your MS1 CPU back in.

I would read and re-read this link that describes the MS2 chip and the older and newer versions of the MS2 card. You *may* have to use a different code downloader for your "old" MS2 green color card. 1.04 may not work, you will have to read up on that or ask at the MS forums.

http://www.megamanual.com/ms2/index.htm

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