Tach failure

I bet it started working when he laid hand on it and hit the starter button
 
Have had THREE tachs on my 2007 Classic. First one my dad dropped on the front crash bars while he was assisting me change handle bars (What can you say, he's your dad!). Replaced with a brand new one ($$$$). that one lasted about 3 years (would move, but between 0 and 3,000 RPM only and got worse). Tried everything to fix, but no go. Replaced with a cheaper used 2005 item (different white face), BUT, still working (Touch Wood).