You may want to look at your fuse panel. Possibly the brake,
If you cannot move the shifter out of the park position then you have a problem with the shifter cable or the brake safety lock. If you can move the shifter to the drive position, and it doesnt go in gear then you are a few quarts low on transmission fluid
It is for towing. You know how you have to step on the brake to move it out of park? Pull that little button and you can move the shift lever.
If by some chance you are asking " why is my shifter stuck in park and you cannot shift out of park " then just turn the key to the first notch, no ign. lights, then put the shifter in neutral, start the car and drive to your local garage. They can fix it for you.
99 and newer tracker have a small oval cover on the left side of the shifter cover near where your right leg would be while driving. Remove the cover and stick in a thin screwdriver to press the small button while shifting out of park.
Insert key. Turn to ACC. Push brake. Push button on shifter. Move shifter out of park. It helps if park lock cable is not broken, and if vehicle is not on an incline.
overdrive off, on a 2003 it is in the end of the gear select lever If it's the hidden button I think you are referring to, should you experience electric release failure (where you cannot get the shifter out of park) pushing this button is a manual over ride allowing you to get the shifter out of park
Wiggle the steering wheel back and forth and run the transmission shifter down then put it firmly back into park.
transmission shift bolt loose try pushing gear shifter all the way back to park
Try putting the shifter in neutral and try it. If not pull the shifter in to park, but pull it into park and turn key.
Make sure the shifter is all the way in park, if it is not in park, the key will not come out. You might want to wiggle the shifter to make sure it is all the way in park.
(1995) ( Geo) ( tracker ),the wheel light comes on with the hubs locked in and the shifter in , but the 4 wheel drive does not appear to be locking in.
Ford Explorer Column Shifter Lever Bracket Repair