If it is just the speedo, you could have broken wires inside at board. my speedo on 2006 K9 has stopped work twice, when I took it apart there were 3 wires going into back of case, I took case apart and the green wire was broken at circuit broad - I soldered and work fine for about 1 year. this year it acted up different and took apart and the black wire needed same repair and works good again. when it acted up, it would work some times and then frezze up, the wires are held in place with a plastic nut and when they break they are right near and sometimes make contact and works a little or jumps around. hope this helps, if it sounds like your problem you are welcome to call me for more info. 717-382-9983 most evening.