The most common problem I see with dimmer switches is that they are blown and won't pass voltage.
I'll do basic "continuity" checks of suspected blown single-pole and 3-way electronic dimmer switches, like a Lutron Ariadne, between screw terminals, with a Fluke 87 meter, which has 40-MegOhm impedance.
This doesn't really tell you much of anything other than that the switch function of the dimmer is working, or if the dimmer is not allowing voltage through.
If the dimmer switch is in the OFF position or blown, the display will always read "OL".
If it's in the ON position the display will bounce unsteadily at around 23 Ohms between terminals.
I'm only guessing that the display bounce has something to do with the Triac firing due to the DC voltage, but I don't do this test any longer than necessary.
