4WD help

i am trying to get the 4x4 working on my truck and after replacing the front diff actuator im still not able to engage 4x4. does anyone know if i can test the transfer case actuator or maybe the position sensors with a multi-meter before i replace the part? im just trying to avoid spending extra for OEM and it not fixing the issue, thanks.

 

Bunch of stuff on YouTube.
https://youtu.be/TmuEVv1neVQ

 

so i kinda followed this video but he doesnt talk about the orientation of the gear in the transfer case actuator. i pulled mine apart and cleaned it and used dielectric grease on the connections but now im having different lights pop up on the dash. i used to have just the 4hi light flashing but now its showing 4lo when i push the 4hi button and 4hi when i push the 4 lo button. im thinking the gear isn't back in the right way but i cant find anything that shows how the gear should be orientated. another thing that is odd is that before i pulled the actuator apart i had both the position sensors unplugged and i could hear the actuator making a noise when the button inside the truck was pushed. it didnt sound like a healthy noise though it was more like a second of scratching almost like there was a gear tooth missing and it was trying to grab it. i didnt see any broken parts when i took it apart though. this is also the first time i have been able to get either actuator to make any noise at all. i replaced the front with an OEM one since the one that came with the truck was a doorman and ive seen where people say they fail pretty often but that clearly wasnt the problem.