Having visited my local Independant Jag' man the other day with a suspension warning lamp showing, he told me that the code indicated a faulty electronic component within the right rear shocker. The ride is fine by the way!
He told me that they are sealed units and not repairable.
Cost for one in the UK is around £400.
I have always had the opinion though that if someone can make something, then it can be taken to bits and rebuilt. Bit beyond my abilities though.