I removed a light fixture/ceiling fan and am trying to install a new fixture. The new fixture has the standard black & white wires and one ground wire. But there are four supply wires - two black & two white, and no bare or green wires. There are two main cables that house one black and one white wire each. I can't figure out how to connect the wires so that the lights work properly. I've tried various connections and the new lights either won't come on or they won't go off.

The old fan/fixture had two pull cords - one for the fan & one for the lights. There was one switch on the wall to turn power on.

Before I elctrocute myself, I thought I'd better *get help*.

 

You have a switch loop setup. One of the cables is the power and the other is the switch. You need to figure out which is which then connect as follows.
Connect the power black to the switch white.
Connect the fixture black to the switch black.
Connect the fixture white to the power white.

 

Do I connect the ground wire from the fixture to the ground screw? Thanks.

TnT

 

I did and it does! Thank You ! ! !

 

Make sure that you correctly determined the power wire. If you mix the two wires up and wire it backwards then you end up switching the neutral, which is dangerous, very dangerous.

By the way, you should have just left the wires the way they were and connected the same two wires to the new light as were connected to the old one. Remember that next time, and it will save you time and hassle.

 

I will - thanks.