4wd actuator questions

Hey everyone, I’ve of course had problems with my 4wd for a while. I have a 2005 sequoia with the center locker. I bought my sequoia with the 4wd not working. The lights on the dash for 4hi, 4low, and the center locker continually flash. I tried to replace the actuator myself and got in way over my head so I bought a used transfer case and put it in. Now it partially works. Just the 4hi and center locker light still flash continuously but I’m able to go in 4hi. I can’t get into 4low and getting out of 4hi back into 2hi is a real challenge. Before I rule out that I got another bad actuator I’m asking for help on any tests I can do. I’ve checked the vent hose on the actuator and it’s in good condition. I took the cover of the actuator and took a peek inside and there is no corrosion or rust inside (although I did see some finger prints on the gears so someone has been inside before). Could this be an electrical issue with the 4wd computer? Thanks.

 

Most likely water intrusion and corrosion on the actuator. There is a thread in the sticky section. Search is your friend on this forum.