Yep, sounds like you've got a bad ground.
Check all connections and it's probably something like corrosion so you might remove the ground and power connections and clean them up.
If that doesn't work, check if there are any splices in the wiring that may have pulled loose.

Send Toolkit a pm, he is good at stuff like this

If you have a multimeter start at the component and work your way toward the battery. What ever is between the last place you don't have 12 volts and the first place you do have 12 volts is the culprit. In my case it was the entire switch panel. bubble switches do suck for sure

Prolly one of those multi pin nylon connectors went bad or came undone.

I have more spare fuses on board than an auto parts store.. Put all of them in a water proof bag and taped them to the underside of my storage compartment for easy access when things go dark. Almost every electrical problem I have had in the last two years has been a fuse issue..Check those terminal connectors as well. Even a little loose can cause you problems.

Buy a voltmeter/circuit tester. Makes narrowing down your search much easier.