A "New"? 355 Start Problem?

Yesterday I was out for a drive with a NorCal Ferrari group, and my car would not start after a planned stop. We got in the car, and there was no electricity. No starter, no fuel pump, no warning lights, no nothin'. It's not really relevant here, but I have immobilized the immobilizer. (The car is a '96.)

It seemed as if the battery was disconnected, but I would swear that it wasn't. Practically the first thing I did after buying the car a few years ago was change the battery, and I can tighten a bolt with the best of them. (Most of you know that you have to jack up the car and remove a wheel to get to the battery compartment.) I intend to do that, but can anyone tell me where to check the other end of the ground wire where it connects to the chassis?

Can anyone here think of another reason that may have caused a complete electrical failure? We had been driving for quite a while above 6K rpm, so the engine compartment was pretty warm. It is possible that some part expanded/contracted to lose connection.

There are still questions, and I don't want it to happen again, but there was a happy ending. The car was parked on a hill in a large, empty parking lot, so why not bump it before calling a tow truck? Tried it once, nothing. Still no electricity. There is more hill, so we tried it one more time, and we drove home with a car full of happy electrons as if there had been no problem.

Did anyone here ever have a similar problem? Thoughts/ideas?

 

Gentlemen,

Thank you for your ideas.
d'alternateur - Je vais demander à mon mécanicien.
Battery Cutoff - I had forgotten that I have one. It appears to be solidly in the 'On' position, but certainly, it could have been slightly corroded.
Fuse block - Which one? Where was the break?
Immobilizer - There is a LOT of info if you do a search. I used an adapter from a Florida company, Specialized ECU Repair. It allowed me to do a 45 minute fix, but it cost $875. (You can still use the fob to lock/unlock the doors, or you can just use the key.)

Has anyone else had any experience like this?

 

Thanks, Beetle. That will be my first check before trying to access & work in that dinky battery compartment. The car starts & runs fine now, but without finding the reason it failed..........

 

Beetle, thank you. I'll certainly try that before I try to dig into the dinky battery compartment. It's starting and running perfectly now, but who wants to drive a car that has stranded you once without knowing the cause.