4lo flashing at start up

Exercised 4wd yesterday now when I start the truck 4 lo flashes until I put the truck in neutral. You can hear the actuator releasing and the light goes out and I can operate as normal. It does this everytime I crank the truck. Something at start up is telling the transfer case to engage 4lo. I've tried driving straight and entering 4wd again, then following the procedure to put it back into 2hi. No change.

 

I had 4LO on startup which if I shut it off and turned it back on it would go away. Then I had an ABS sensor go out and after replacing it, no more 4LO error.

 

Did you get a separate abs error or was it something you diagnosed?