Bought used 1997 F 250, electronic 4 wheel drive is not working
Transfer case shift motors are known failure component on Ford electronic shift, you might try this: locate the motor on transfer case and with a small hammer lightly tap on the motor while someone pushes the 4X4 shift button, if the motor runs and shifts then you have found you problem, if the motor doesn't run then you need to trace out the power and ground pathways to and from the main control box under the dash pad on the passenger side.
Turned out to be the GEM module.
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