MASE.....it sounds like you might need to lubricate the cable that operates the whole thing.
It's the lock itself not the cable. The last tiny bit of it will not turn enough to pull the lock open to fully release the seat tab.
ETA - I also noticed that the locking tab on the bottom of the Mustang seat moves about 1/16th of an inch which may be grabbing the last bit of the lock.
Same here.
I opened hole system and I'am pretty sure that the cable is stretch out...
Lock is turning all the way but it's not enough. The locking tab isn't open enough.
Have to do something>probably not so hard to fix by some mode...