Do you have a fuse between your battery and your DC panel? Get your digital voltmeter (DVM) and start at the battery looking for 12V. Follow the wires and check continuity across fuses. When it changes, you've found your culprit.
I just had a similar incident this morning and found a blown fuse at the house battery. Simple fix to a problem brought on by my own mistake. (nevermind, it's a very long story...)