I plowed with the hubs manually locked and did fine, don't know if both hubs had power or not but figured plugging the line would cure the problem, at least to get the shift on the fly working, at least to one wheel. However I'm not sure the vacuum control solenoid is doing it's job. With everything hooked up the heater defaults to the defrosters, if I activate the 4wd, the heater will act as it should. I'm wondering if there is another componet that is preventing the correct electrical charge from being sent to the solenoid. There is one plug with 3 terminals....
Sorry for the late response, had to run out, back now. pulling my hair out,,,,