Red blinking 4wd light flashes , no fault code , goen in and out of 4wd normally

Yesterday, when I started my car, the 4WD indicator started blinking and then stopped. I tried to start in H4 and noticed it was not possible, and when I turned the knob to L4, it did not work either.… 

No light & no transfer case engagement when shifting to 4L or 4H

4wd! Keeps flashing on dash but 4wd isn't on

4wd switch not turning on no lights just off

I HAVE A SIGN ON CULSTER (ABS)
AND (SERVICE 4WD)
The 4WD not working