Hello everyone. New here but I’ve been a model railroader my whole life lol. I got a K-Line 120 dual signal bridge at a flea market a couple weeks ago ($10 woohoo!) and after some trial and error I got it working just to test it out, as i don’t actually have a layout at the moment. The problem is that it’s opposite from what it’s supposed to do. The right side signal is red, then turns green when the train hits the isolated rail, then turns red again once it clears it. The left side signal does the same thing except the red light stays on the whole time. I tried swapping the wires around but same thing. I’m sure it has to be something dumb that i have hooked up wrong. If anybody has been there before and knows what to suggest it would be highly appreciated. Thanks!
Welcome aboard Charlie_Harper! 
At some point in time every one of us has been stumped by something that just doesn’t make logical sense. So don’t worry about that! 
I don’t know the K-Line signal bridge, but do the bulbs come out?
Thanks. Yes they are the threaded base types. I actually just got some Town and Country LEDs I’m going to put in it so I don’t have to worry about them getting hot and melting the plastic signal heads.
If you switched the bulb’s positions then wouldn’t they light in the correct sequence? Red for the occupied block and green for a clear block?