Sorry if this has already been asked. found it discussed for 3Gen models, but not 4Gen.

Snowed yesterday so when i get in, i put it in 4H. nothing happens, and lights flash for 10 mins. did the stop and neutral, put in reverse, etc. and nothing worked. usually it engages within 15-20 secs. it just flashed and never engaged. then, i tried pushing the VSC Off button and nothing happens, just a clicking noise around the glove compartment. Is there anything i can do to fix it, or is it a serious problem.

2004 4Runner Sport 65,000 miles

 

Sounds like either the front ADD actuator isn't actuating or the Tcase actuator isn't actuating.
Check the FSM on NCTTORA and it should have test procedures.