I have a 2000 TJ too, and had this same problem with the tack and speedo and all the other needles as well. It would also give a "No bus" code in the odometer window. I pulled the gage cluster out and cleaned the pins and female receptcles with a soft tooth brush, then I took a jar of vaseline and a cotton swab and put a dab on each pin and in each receptcle, wiped off the excess, and put it all back together. It has worked great ever since. the vaseline helps make a better contact, will keep moisture out, and will keep corrosion from forming on the cantacts. Old aircraft mechanic's trick.