Headlight wiring question

[Shoe]

I have a 97 Legacy that I have a problem with. The passenger side headlight works fine on dim, but when I hit the brights, that side actually dims. Today I changed the bulb, and also the plug since it looked a little cooked. The plug had already been replaced before. The new bulb acts just like the old bulb; it gets dimmer with the brights on. I hooked the old bulb up to the plug outside of the headlight, and on brights the bottom half of the bulb is barely lit, the top half is out. Plugged into the drivers side, the top half is lit on dim and the bottom half is lit on brights, so I know the bulb is good. I'm wondering if the last owner wired the plug wrong, and I just coppied their mistake. Can someone look at the wires on the passenger side headlight and tell me which wire goes where? The original wires are red, black, and yellow.

Thanks,

Mark