[Q] VEGA IRON 870 Continuously Vibrating even it is switched off topic

I have Vega Iron 870L the Korean made phone and it has suddenly start vibrating and keep on doing it untill i remove the battery.
Phone is working fine with all of its functions.

I tried once to become a smart man and open the back to check the vibrate motor because i was assuming there might be some wet area so i could dry it but it was not the case.
Suddenly when it was on legs on the chairs it fall down badly..... apparently nothing happened put the battery again it was all ok by then.... no vibration every thing seemed correct by that fall........ phone started working.. :) :)

but suddenly again today when i put charger cable inside it start vibrating again........... so right now even the phone is switch off.... not on charger it keep on vibrating........

i need help..................!!!!!!

THIS IS MY FIRST POST ON THIS FORUM SO GUYS PLEASE HELP ME>............................................