[Norretal]

I can't offer too many suggestions on what it is but I can comment on what it's like to lose the power steering on one of these. I had a burst hose and it dropped the fluid suddenly on a journey. If you can still steer but it's heavier than normal then I'd go with tonupkid and say your level may be low. When I lost mine it was a massive effort to even turn the wheel, I remember doing a twenty point turn in a cul de sac that took a LOT of effort.

Hope you get sorted quickly, and cheaply