Hi Bill,
I had the same problem after annual in April. Mechanic talked to Don M., replaced ignition switch, SOS, P leads points in Left mag and then sent the 50 hour Left mag back for check. The engine shop found no problem with the mag but on general principles did replace the starting points again and OPENED THE POINTS MORE. It started working. I really think the problem was that the points needed to be opened more, The ignition switch was worn and we burned up the SOS module trying to crank it. Kevin, my mechanic and I were talking about this today. Kevin did the right thing and ate many hours of labor and the parts. I researched this probklem on the Mooney Tech site and others have resolved the problem without finding a "smoking gun". I really think my problem was that the starting points in the left mage need to be opened more. If you want to call me 919.819.3451. We wasted 3 weeks trying to fix it.
Eddie