Found this inside all of my trafficators. Discovered while troubleshooting a short causing my Ammeter to bounce to extremes in time with my flasher.
Apparently, the wrapped wire will eventually work loose and slip, making contact with the center terminal and bringing on the resultant short.
Fixed all of them this way, and problem solved. Add a small terminal to the end of the wire and pinch between the bullet housing and the lamp support. Just be sure to snug it down nice & tight.
I could have soldered it, but wanted an easier removal, if necessary.