I have a 2001 ranger 4.0ohc, auto 4x4. the 4wd has not been functioning for quite some time, and i have narrowed down that the shift motor works properly, and that the is no voltage to its wiring harness. Due to cost is there a way to test the 4x4 control module and switch to narrow it down further before I drop a lot of money into this? Sadly i am on a limited time frame for the fix ( like i have one week to have the truck finished here in Illinois and be on the road for Arizona.) Any and all help will be greatly appreciated.