Speedometer intermittent failure
 

960 estate 1992 2.3 turbo petrol automatic. Is it possible to - garage says rear sensor ok but cluster irrepairable. Does anyone know better or is the only alternative to purchase a unit to plug into cigarette lighter. When it is not working the mileage meter obviously does'nt work either so concerned about legality. Any help/advice appreciated as otherwise she is running perfectly.

It is repairable. Most likely it is the capacitors in the speedometer that are going bad and they can be replaced. They are cheap but the labor involved is fiddly and should be done by a specialty shop that specializes in electronic soldering and such.
https://www.volvoclub.org.uk/faq/Ele...eterRepair.htm

Thanks for the info on speedometer repair.