Put my 2002 Ford F150 into 4-wheel-drive and cannot put it back in two-wheel drive why is possible cause?
Try this: make sure you are on a level surface, block the wheels put trans in neutral, with the key turn on have someone push the 2WD button while you lightly tap on the transfercase shift motor, you should be able to hear it run until it get into 2WD, if it doesn't run then you will have to remove the shift motor assembly and manually turn the pawl to the 2WD position, then cover the hole with some Duck or Gorilla tape, then at least you can drive it, until you have time to run a diagnostic on the 4X4 shift electronics. HTH
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