740d steering effort changed

Since yesterday noon I get the message, which is to be seen on the picture constantly as soon as I hit the steering wheel fully on one side. Just before the message occurs the steering wheel will be short harder to turn. However, the message does not always come, I would appreciate in about 70% of the cases. Does anyone here perhaps know what that could be? I have already read the error memory with the Carly Adapter and another device, however I find no error which on me the problem.