I intentionally ran my left tank down to test the low fuel alarm. I got no warning, either audible or via the annunciator light. My ENGINE.AFD file contains the following, confirming that I should have received a warning below 2 gallons remaining:

TANK_1.MAX, 200
TANK_1.YELLOW_LOW, 40
TANK_1.RED_LOW, 20
TANK_1.UNITS, 0
TANK_1.ENABLE, 1
TANK_1.AUDIO, 1
TANK_2.MAX, 200
TANK_2.YELLOW_LOW, 40
TANK_2.RED_LOW, 20
TANK_2.UNITS, 0
TANK_2.ENABLE, 1
TANK_2.AUDIO, 1

Anybody know why this isn't working? It looks like I have the tanks enabled, and the audio enabled too.