I had the same problem with my e32 v8.
I had some trouble firguring the cause...worst case scenario, gearbox mau kong but in the end it turned out to be something minimal.
First, try this - Check you battery condition . A weak battery could be the case. My car was running on a din 55 battery when it should be a din 88.
If it's not the battery, then try sticking the gear into 4th gear and see if it goes into failsafe mode again. Mine funtioned normally when it was entered into 4th.
If the fail safe mode doesnt appear, it means you have a loose cable.
It's been more than a year since I had the problem and my gearbox is perfect for now.
Cheers!