1998 Ford Explorer stuck in 4 wheel drive high how do I get it out?

1998 Ford Explorer stuck in 4 wheel drive high how do I get it out?

I've checked the electric motor seems to be working but can't get it to shift back into all wheel drive 2 wheel drive shift on the Fly 4 liter 6

Make sure all of the tires are the exact same size. Check the numbers on the sidewall. If you have a different tire it can keep the 4WD from going back to 2WD.
If the tires are ok go to the dealer. They can scan for transmission and transfer case codes to make sure all of the switches and solenoids are working.
An OBD II scan tool/code reader can't read transmission codes.

Disconnect and plug the FWD vacumme actuator hoses to the front axle differential actuator.
Possible stuck open vacumme control valve or broken front axle engagement fork return spring.
Jack stand the wheels and verify the front axle is engaged, possible bad transfer case light switch.

Removing the power wire to the vacumme solenoid is useless if the solenoid valve is stuck open.