Right signals don't work when lights are on

[Sock]

Hey, i got an 86 halfton w/ 305 2wd. My right signal doesn't work when i turn my lights on, sometimes it will click once and then stop but if i turn my lights off they work perfectly. Has anybody experienced this problem before?

I also have a connector i am unsure about under my hood. its near my brake booster. its a green wire with an orange connector.

[Captkaos]

Check the bulbs and then check for continuity or grounds..

Need a better pic of the plug, where does it go?

[jetmech]

I would clean ground wires on the radiator support and frame near the battery. The orange connector, I've been told, is some sort of test port. It is on my truck also and has nothing plugged into it. Others here can correct me if I'm wrong.