Are you sure you shouldn't be plugged into A, instead of 10A?
Every other scale seems like it should be in the hole identified by the print that wraps the edge of the dial.
At any rate it's NOT 10A draw, so it will be safe for the meter to put it in the unfused A socket.
If I had to guess........
But I don't.
1.9A would kill the battery in a few days.
Try a test light.
Make sure the doors are closed.
Check the diodes in the alternator, or disconnect it and see if the reading goes away.
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.