hello guys few days ago i had an e39 with transmission stuck at 4th gear which is limp home mode.
fault codes showing in control unit 2 of them were front left speed sensor and rear right speed sensor so i replaced them and now abs and asc are working good.
but still when i turn car and drive for 2-3 minutes the transmission returns to limp home mode.
there's still a fault code 64 that has no description not in any website neither in ISTA/D
i am wondering if anyone of you had the same problem and what is the solution please.

thanks in advance

 

Are you sure it's not fault code 54

54: Torque Converter Lockup Clutch

 

I had issues with "limp mode"

It ended up being a bad neutral safety switch.

the car would switch to random gears while driving. The indication on the dash and gear selector would be random and different. Sure sign of the neutral safety switch going out.