I've been working on a 96 XP I just bought. It had zero power to anything. It would beep once and that was it. I had to replace the mpem on it. I did an aftermarket one from bay area powersports. After that it fired right up.
I also just replaced the mpem on a 98 GTX limited that everything worked "except spark" single beep at first then paid for a key and programming, still no spark. After replacing the mpem I got spark and it beeped twice. Fired up and ran. It seems like the mpems go out all the time.