Where can i check decimal precision of pricelists and currencies?

You have to activate the developer mode to see the options.

I found these options. I changed tax rounding method to globally, but its ignoring me.

If i change precision to 00,001 odoo shows prices with 3 decimals.

Why its ignoring me?

There is another setting, which I have amended to my answer, decimal accuracy, check this also. However, somebody obviously did change the settings in your system because out of the box Odoo works properly with 2 digits and proper rounding.

Or did you install a module such as "Swedish rounding"?

I didnt install an other country module. This is spanish mod. I have developer options actived but can't find decimal accuracy. Only rounding factor.

Thanks

"Swedish rounding" is not a country module, that's a special rounding (5 cents rounding).

See my amended answer for the decimal accuracy.

Decimal accuracy is set to 2 digits for product price.

Then I do not have any more ideas than just completely updating your Odoo instance. Either you or somebody else did manipulate the original settings either manually or be installing a module.

Where can i check if sweedish rounding is active??? Thanks

You must have installed a module like https://www.odoo.com/apps/modules/8.0/smile_decimal_precision/ in order to have swedish rounding, or have a rounding factor of 0.1 in your currency definition.

i have not installes any modules for change decimal precision. Also, rounding factor is set to 0.01 and rounding for taxes is set to globally and not "per line". The option is set and saved. I reboot the server and didnt change anything. Its ignoring me.

Its Odoo9.

You have messed up your instance, don't ask me how and why. It is properly working for thousands of installations. Look at your logs if there's anything suspicious, else try to update your instance and see if it works, otherwise I would recommend you a new clean install.

its a new install, its tunning for only a month aprox. I dont understand. Its installed over debian 8.

how can i try to update the instance without losing data?

Sorry, but this goes already far beyond my capacities. Do a system image, make a backup of the database, do the update (be sure you know how to do that), hope and pray.

Thanks anyway Ermin.