98 ford expedition light is on 4 low i turned switch on dash to 2 wd light does not change and will not come out of 4 low

It could be your actuator valve sticking,4 wheel drive Works off of air. Try checking your hoses for cracks or leaks around the actuator valve for the 4 wheel drive. I think that the actuator is on the front axle it will be a little box will have air lines running to it.checked and make sure they're hooked up,not broken or kinked. Check the harness hook up also. Fuses,ext...hope this helps.

My expedition sticks sometimes. To get it to unlock I slowly drive to a gravel parking lot, drive in reverse goosing the throttle, then drive forward gooseing the throttle. Sometimes it takes 4 or 5 tries. The problem with mine is the transfer case solenoid gets used so infrequently that it sticks when the auto 4×4 decides it needs all the wheels for something momentarily.