Our company system team is going to change the Active Directory password for the SharePoint system account.
I need to know all activities I need to do post password change.
If you change the password and update the SharePoint with new password, after that make sure all app pools and timer service gets the new password. Update a sync with new password, then you are all set.
I don't see any impact if process properly followed. Worst case scenario would be SharePoint goes down if you locked out the account.