What happens when you fail to pay bank loan instalments?

If the borrower failed to pay 3 consecutive instalments or 6 nonconsecutive instalments of the monthly instalments without approval of the bank, then ALL the instalments, interests and any other fees become DUE AND PAYABLE IMMEDIATELY without any notification or any court ruling (this is under the Central Bank approved standard loan forms which you have signed).

The bank may in all likelihood pursue a legal case (criminal and then civil) against you for default as well by depositing your security cheque which you provided at the time of availing the loan.