Welcome to Matthew's Volvo Site. The speedo sender unit is mounted in the differential housing. Check that the wiring is intact and making good contact. It may be that the terminals need cleaning as they are exposed to lots of dirt and salt. Bill. bill, i had the speedo sender unit checked and its ...

Thanks Bill, I'll let you know if that fixes it[/quote]

my 240 speedo moves sometimes and sometimes not. when i hit a bump it wants to work then goes back to zero. any idea what the problem is? and how so you fix it?