2007 4runner v6. In 2wd no lights on dash when shifting to 4hi both lights flash on dash and when in 4lo buzzer sound. 4wd of course isn't engaged. Swapped out front diff actuator and the problem persisted. Can manually slide collar and get front axle to engage when ADD actuator was removed. A buddy removed a small plate on bottom of tcase and pushed some sort of button looking thing. Now the front diff light is on all the time, locking differential light flashes constantly and using the selector switch doesn't change anything. Lights are on constantly even when selected to 2wd mode. No buzzer now in 4lo. Front diff definitely still not engaged. Almost as if the switch is no longer doing anything. Limp mode of some sort or bad tcase actuator? I pulled fuse for 4wd ecu which causes a bunch of lights on dash and then reinstalled. No change.