Loose battery cables... Easy check.
Coil... Over a hard bump, yes. Not with a keyfob and starts again... check bank account.
The HMAN Hit List:
1. Connector not connected - HMAN found the easy one.
2. Wire out of connector - say the coil wire is one wire not connected we think one wire attached how?
3. Short to ground/signal out of range - we have an H kind of controller module?
You are not saying how long this happens between rounds. Days on end and nothing but miles on the bike is not looking like loose parts, but the controller? So you'd have to run the 1-2 Hit List and get that out of the way none the less. You know it's not short to ground because it comes back on line with a key off, key one clearing the controller's glitch to ground, or lost some sort of bug in that controller design.