Have you checked the connections to the Power steering unit ( just about where your knees would be, when sat in car). There are 2 connections, unplug them and make sure there clean and plug back in. If this doesnt work, I would say your electronics on the power steering unit are fried, which is very common, but very easy to fix. Your hardest job would be to find another to fit. I changed a unit on a Stilo 1.6 active 5 door, and i managed to find a donor unit on ebay for £135 delivered and it worked with no problems at all. ( no need for any resetting at fiat ). I went for one with the same part number as my original one, but some people say any will fit, but other people say, it must be from the same door model, ie. 3 door or 5 door and others say it must be the same part number. But from reading other stories on here, it appears they are interchangable. If you cant get one with the same part number, I would go for one which has the same features on, ie. asr and so on. And hopefully it should be fine.