Lighting – Why won’t the bathroom light fixture work

I'm going to take a wild guess that the previous home owner put the blanks up because they had the same problem and didn't want to fix it. You likely have a short circuit and need to track down where the short is occurring. I'd remove the bulb from the fixture, unhook each of the wires that you connected before, and use a multimeter to test for "continuity" between the wires on each run (e.g. hot to neutral, hot to ground, neutral to ground for the line to the switch, for the light fixture without a bulb, and anywhere else that was previously disconnected). If you don't have continuity with a simple low voltage tester, then the problem could be arcing that only occurs when 120V is applied. Either way, get this fixed before turning the breaker back on with this fixture wired.

It sounds like you have a fixture controlled by a conventional dimmer and are using CFL non-dimmable bulbs.

Standard dimmers were designed for incandescent bulbs. Many CFL and LED bulbs are non-dimmable. Some are dimmable, but only work with special dimmers designed for their electronic circuitry (conventional bulbs have no circuitry, only simple filaments). Some CFL or LED (not many) will work with a standard dimmer.

First you need to make sure the bulbs are dimmable, and then that you have a compatible dimmer.

In general, CFL and LED bulb packages indicate whether they are dimmable or not. If it does not say dimmable, it is probably not. Dimmers also indicate whether they are intended for CFL and/or LED bulbs. Again, if it doesn't mention CFL or LED, it is probably not compatible, unless you have bulbs that specifically say works with standard (or conventional) dimmers.

Check the fixture by using an incandescent bulb. If it works, either go with incandescent, find CFL or LED bulbs that work with standard dimmers or swap out the dimmer.

If the incandescent doesn't work, you have a wiring problem or a defective fixture.