Hey guys, fairly new to posting here but need help figuring this out!

I have a 2001 4runner sr5 4wd. Ive only had it for about 6 months and with winter rolling around 4wd has been on my mind. The car has about 230k on the body but the engine is fairly new.

Anyway, I've been having problems with the 4wd lately. Last week the 4wd on the fly button wasn't working so after reading forums and doing some research I flushed and refilled both the front and rear diff last week. That seemed to help as now the 4wd on the fly button works 9/10 times on engaging the AWD feature.

However, now im having problems with the CDL. After I press the button and work it into 4Hi by driving forward or reverse it'll eventually lock. The yellow light on the dash in the center becomes solid. Its locked and the VSC off light comes on too. However a few seconds later, maybe 10 or so, the dash lights start flashing, the VSC off light disappears and the vehicle goes back to just the 4 green wheel lights being on...

Cant find anything on this so please help!