I had the jumpy needle issue and it was the contacts where the speedo plugs into the power pins on the instrument panel. Those are the same contacts that the temp compensator board uses looks like to me. Anyway if you bend in the spring contacts so they make solid connection that seems to have fixed the problem.

But it also sounds like you may have wiring issues on the not working at all problem under there also.

Good Luck,

Paul

Dollars to doughnuts that the wire going into the speedo sensor is broken at the rear diff housing. Jack the rear of the car up and look at the wires running to the diff pan. These are the speedo wires. Look for cracked insulation.

The motion of the rear axle moving up and down causes the speedo to work intermititantly and finally to break.

I've had this problem on multiple RWD Volvos in our fleet and everytime it was these wires. Just cut the old wire back far enough to "good" wire and crimp on additional wire using the original connectors. You can remove and re-use the connectors by separating them with a jelwer's screwdriver.

Good luck and post back your findings.

what hose? somebody's confused.

it's completely electric, from the sensor in the diff to the speedo itself. i suspect a loose connection at the cluster. tighten all the screws on the circuit board and make sure all the connectors are tight. peek at the sensor and make sure the connector isn't trying to fall off. it might be the sensor itself going south. easiest way to find out is to LET IT FAIL. that way, no one's chasing ghosts while it works sometimes. good luck, chuck.