Forward Control Module

Intersting problem maybe some of you have heard of. I have a 2001 Grand Caravan with a 3.3 in it. Last week, cranked fine but wouldn't start. Error codes showed recently disconnected battery and auto shut down (ASD) circiut problems (battery has not been disconnected that I know of). Ran the diagnostic tests in the manual, and ASD circuit tested fine. Had it towed to the dealer, and they found the same codes, but no problem. When they started a more in depth troubleshooting procedure, the problem healed, and they couldn't figure what it was (not faulting the dealer, these intermitant electrical/computer problems can be tough), but they recommend changing the forward control module (FCM) and the power dist box (I believe this is the IPM fuse box). They want $700 for the job, but I'm leary of just changing parts hoping it makes the problem go away. Any one out there have a similar problem, or any ideas on this?