Z4 2.2 power steering problem

[Derwent74]

I've just got a 2004 z4 2.2 and after driving it for a few hours with no problems what so ever, I parked up for half a hour went and started it again and the power steering light stopped on and the steering was stiff, i then left it for another half hour, started it again and all was fine. This process has repeated since. I've read all other owners issues and everyone's seems to be different issues, please help. Thanks

[greg81]

I had this on a couple of occasions. I replaced the ageing battery and all was well

[Derwent74]

Thanks that's worth a look