Another diff lock question

Hi.

I know this sorta thing has been covered before but i cant find the right answer.

I was driving with the central diff locks in and got out of a sticky hole. I then turned diffs off. But the light didn't go out. I then drove on at slow speed. Then there was a loud bang and the diff lever jumped into neutral.

Anyone know what happened here? Do you have to 'unwind' the diff?

Cheers.

diff lock is engaged by a spring on its selector shaft as it is just a collar that slides onto diff ,and once preloaded by you selecting difflock engages when splines line up hence ability to put in on the move ,when you disengage difflock with lever you preload spring opposite way and will pull collar of diff when load is relieved,sometimes you may need to reverse a little if load or wind up in transmission,if load isnt reduce spring wont have enough force to move collar and extra stress in system can either relieve it self by spinning wheel or breaking weakest part ie uj or half shaft or in your case kick trans box out of gear ,hi/low gears are held in gear by triangle shaped dog teeth on gear and selector hub these wear over time making jumping out more likely under high stress,make sure your light works as this is an actual indicator of were difflock collar is and so you know if its stuck on obviously lever isnt