"PNP switch" implies that the transmission did not know what position the shifter handle was in, hence confusion on part of transmission, hence error code.

Unless you're eager to throw money at the problem, my advice is that you turn the ignition key just far enough from the OFF position so that it is possible to move the shifter handle to various positions. Then, hopefully with everything still off, run the handle through all the positions (all the way forward to all the way back) repeatedly (brisky but not violently). Maybe 20 times?

Make sure the error code is cleared.

See if you can use the car normally.

Notice if the shifter is where it belongs, ie, if it falls into the proper position almost by itself at it finds the "detent" position(s). Keep in mind that if there is slop/play in the shifter cable, the switch at the end of the cable will wind up in a different position depending upon the direction the handle was going when the detent position was reached.

Good luck.

BTW, 24 hours is not at all a long time for my car to sit unused.

- Dave; '95 854T, 139K mi