I have seen myself and also from some of the members here that there is a difference PF Balance between Member Passbook and PF CheckBalance (Some have remarked it has been updated only till March 31st, 2015)
So always log into Member Passbook to check your PF Balance – Click on the link about how to access Member Passbook
Whenever you check Balance, Please go to Member Passbook to check your PF Balance to verify it!
Note : I have seen myself there is a huge difference between in Balance between MemberPassbook and EPF CheckBalance
MemberPassbook always displays the correct updated Balance