I have a 2000 V70XC and intermittantly the speedometer falls to zero and the odometer display goes blank.
any hints would be appreciated.

 

Is the ABS light on?

If so then the ABS module is bad and most likely causing the issue.

 

I have a 2004 XC70 and had that problem, randomly the whole instrument panel would short out, the car would run fine, but there was nothing, then at a random interval it would come back on, but the ABS warning light would come on. Took it to the dealer 3 times before they figured out it was the wiring harness below the drivers seat had become frayed from the seat moving back and forth between my wife and I driving the car. They taped it up and added substantially more fowm tape as was stock, haven't had a problem since.

Worth looking into.

 

tech- thanks for the advice on the ABS module. This is my sister's car and descriptions are difficult to get.(she lives 800 miles away) The ABS light is on but apparently the entire cluster goes dead. Still thinking ABS module?
Thanks again from a Toyota tech.

 

Yes I do. Those cars are somewhat networked. If it goes bad it can play games with the other computers.

Search on here there is some places it can be sent to and rebuilt for pretty cheap.