Open a bank account

Short answer. No.

There is a longer one but it gets the same result.

Banks should ask for a copy of your KITAS or KITAP.
To open an account without one isn't legal.
Question is, why would a short term visa holder want to open an account?

“It is possible to open a bank account without kitas?”

Generally the correct answer is no, however, it is possible.  However, you will need to be able to prove to the bank that you are in the process of KITAS application.

Indonesia is not an off shore tax haven, and it is a participant in anti money laundering efforts by way of cooperation with Interpol and other international legal authorities.  Bank accounts for foreigners are intended only for those who will be taking residency in Indonesia.

No in fact I ask for a visa one the year to begin and if everything agrees me to settle down definitively