What type of PIN? And why are you trying to bypass it? If it's the 5-digit signing PIN, that can be any 5 digits of your choice, except it cannot be all zeros.
Or are you referring to a 6-digit IP PIN (Identity Protection PIN), provided by the IRS to victims of tax-related ID theft or to people who voluntarily opt-in to the IP PIN program?
Or is it something else, such as a state PIN?