Error message
 

I have the message ' Position bulb fault' What and where is a position bulb?

Cheers

it just means that a bulb is burned out somewhere on your car.

Position Bulb is one of 4 tail light bulbs on the S80. You have one or more burned out. You might also check to make sure all four match.

Thanks guys, I'll check it out this morning. I also have ' SRS service urgent' but I assume that is a job for Volvo

Quite interesting, I replaced the defective bulb on the back lights with a one same wattage etc but more bulb shaped. It worked but the other 2 on the r/h side went off. I went down to Halfords and bought 4 good quality identical bulbs and all is now okay, apart from 'SRS service urgent' which I assume is a dealer job

Yes the SRS is dealer or a shop that can read the SRS codes.