96 base 850, abs/trac lite issue, speedo was OK, odo not working. Initially tried to fix abs unit with soldering iron. When reconnected still have lites on and now speedo climbs to 47mph as soon as you start moving and stays there unless you stop or exceed 47mph where it starts reading proper speed. Replaced abs and lites off but speedo still the same. Replaced odo gear and no change. Looking for ideas on what to check next. Thanks for any help.