Help! My left Shimano 105 shifter stopped functioning suddenly. The large lever clicks, but doesn't move the cable. The small lever moves a bit but won't click or move the cable. When I look into the shifter housing, the end of the cable is way in the outside position (totally visible rather than way back inside).
It worked fine yesterday. Today, I changed my chainrings, chain, and cassette. When the installation was complete, I was ready to adjust the high-low settings and the cable tension, the left shifter just wouldn't work. The gears changed easily by pulling the wire, but the shifter won't do it.
Any ideas of what happened and what I can do to fix it?