The OD problem could be completely unrelated to the fluid change. It's engaged by an electric solenoid that turns on a hydraulic flow path. The relay that activates the solenoid is troublesome. Replace it or pop it apart and re-solder its circuit board. Part number 3523804.
It's also possible that the wire has grounded against the trans and blown the fuse, or the solenoid itself has collected a small bit of dirt blocking it. WIth the engine off but ignition on, have someone cycle the pushbutton switch while you listen near the left side of the transmission, under the car. YOu should hear a click as the solenoid turns on and off. If not, it's electrical.

The solenoid is the front right one on the fuse block. REmove the ashtray and the coin tray/ cig lighter above it to access. It's a tall skinny relay. Just plugs in. Could simply not be plugged in all the way, see if it clicks when you push the shifter button too.
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Rob Bareiss, New London CT ::: 'Roterande Fläkt Och Drivremmar!'