Issue with the M

On Sunday I took the 512M out for the first time in a couple months to the Enzo birthday thing at the Petersen Museum. Wanted to check my tire pressure so stupidly used my socket powered pump. Plugged it into the cig lighter and it was fine, added about 3 psi to three tires.
When I got around to the last tire the pump went dead and all of a sudden the buzzing noise that comes on when the door is open and key is in came on. And it won't go off unless I take the key out of the ignition.
Everything else was working perfectly except the dome lights so we decided to head up to the Petersen. The car drove flawlessly other than having to put up with the buzzing the whole drive up and back.

I wasn't planning to take it in the my tech for a few more months for a full service and will get it sorted then if need be but has anyone else had this problem or know what it could be related to. Fuse panel is going to be my first look.

 

Thanks very much! It is even better to drive than to look at

 

Thanks very much for the link