2000 Montero/ Pajero transfer case

[paj2000]

I have a 2000 Montero/Pajero and after a day's 4 wheel driving I can't unlock the hubs, when I first go from 4HLC to 4H the orange light keeps flashing after several attempts or turning the car on and off it will go out but when I go to 2WD the green lights won't stop flashing, I try reversing turning the car off and on but they won't stop flash so I drive home in 4H, when I get home and reverse into my driveway the car grinds to a holt, then the next morning after several attempts it will go out. It only does it after a lengthy 4X4 session not when I take it to the dealer and he takes it to the local park it works fine. When it was under warranty the dealer replaced a motor above the transfer case which seemed to fix it but now it's back and the car's out of warranty. Would it be this motor again or something else?