I have an omron LY2 12vdc acting as a relay for a projector screen. I wasn't able to get the screen to move so unplugged everything from the relay (without taking note of how they were plugged in to begin with), and tried to connect the two sides of the power cord to see if that would elicit a reaction. One side of the cord however is 4 wire (connected to projector) and the other is 3 wire... I don't know what to do with the extra red wire and I don't know how to plug it all back into the relay, any ideas on the subject would be appreciated.
Thanks.

You are going to have to dissassemble the switch to get the color of the wires used or do some resistance test.