These go wrong after the trip counter button is pushed in while the car is in motion and the gears mis match in side .I used a drill to hold the gears and number drums in place plus tape across all the numbers .If they move it takes ages to get them right again , this is the one main part to remember . Push the drill in [the same size as spindle] I then put groves in the spindle and super glue.to secure it .And be very carefull lift the pointer off .Take pictures of it, if you can , and make sure numbers are the same when your finished. I was very lucky , a friend sent me an old speedo to operate on .So i knew the ins and out of the job when i started to work on it if you want help it is all on this site .in tech info above...