dash message - trans failsafe prog (help!)

[BMW DIY Guy]

Hey yall

2001 E53 with 140k miles on it just for reference, and extremely well maintained.

Fired her up yesterday and started to back out of the garage and got the dreaded dashboard DING! and then a fault message. The reader display says "trans failsafe prog". I immediately went back into drive, and put her back in the garage. Being an IT guy, went for the "have you rebooted" option and stopped and restarted several times, but the code remained.

I pulled the ECU error code, and it is:

Current Fault Log
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ECU reports no current faults

Pending Fault Log
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P0763: Shift Solenoid "C" Electrical


So this sounds like a failing shift solenoid? This isn't something I am familiar with on the car. My partner also just let me know she saw like briefly, like 6 months ago while far away from home. Got the message on start, stopped and restarted the car and it went away immediately.

Lastly, the car fired up perfectly this morning and still good after a short test drive around the neighborhood.

So.. failing solenoid? Forum search didn't come up with anything, though maybe my forum-fu is weak this morning.

thanks yall, hoping something simple and easy, as timing couldn't be worse for complex and/or expensive.