My issue was solved with the E diff solenoid replacement
Still having this issue - I am going to check the bleed screws on the actuator. Really running out of things to eliminate...
windsock, your response early in this thread is very good and clearly shows that you have rare knowledge of the operational logic and fault protection in this system. I have a similar problem on my 07 - after warming up, the unit goes into 2nd gear limp mode and the red light for F1 Gearbox comes on. The dealer tells me that this system can be repaired part by part, but full replacement of the F1 unit will be the end result. If there is contamination just like you said, it goes throughout the entire system. Do you have any idea of what causes the internal contamination that leads to F1 failure? I hope is not introduced during the annual service fluid change. Thanks
