So I was getting into the car after my sis had just driven it, in her seating position. She leaves the car with her master key in ignition position #2 where all systems are on except the engine is off.

I get in, turn on the engine, and wtf??? I can't adjust the seat. None of the seat buttons work, memory buttons don't work, and the passenger seat can't be adjusted either. I turn the car off, try the valet key, but it doesn't work either. Try my master key, doesn't work either. Everything is still working perfectly except the seat adjustments.

Now my sister has to drive, since I don't fit. When we pull away from the curb, we notice that we cannot turn off PDC manually after its been activated. We have to wait for it to go off by itself.

We drive for about a mile and then stop the car. I try all the keys again, thinking it might have something to do with the memory or something, but doesn't work. I get out, lock the car with my master key, wait 20 minutes, get back in, AND THE SEATS WORK! PDC too. Everything's back to normal.


Is there an explanation for what happened?
Some sort of glitch?
Anything else I could've or shoud've tried?

 

Yes, likely a glitch of some sort; you probably should have tried rebooting iDrive, which you can do since you have Pro Nav: hold CD eject, DVD eject, and radio mute (press the radio volume knob) simultaneously; this forces iDrive to restart.

 

I don't know about the PDC but I also don't seem to be able to use the memory seat button to restore to my position if I was using my wife's key, and vice-versa. I never bothered to check so I don't really know if this was always like that. But then again if that's the case, what use is the memory setting?

You could have tried double unlocking using your key. The seat should at least reset to your preset position. If not locking with your sis's key and unlocking with yours (or double unlocking) should do the trick.