This is the second violation, the first was also a summary....but I heard the laws have changed
Criminal Defense Attorney
Summary offenses in Pennsylvania can carry a sentence of up to 90 days' incarceration.
Whether your particular offense would result in jail time upon conviction and sentencing will depend on the nature of the offense charged, the circumstances of the offense, and your criminal record.
Also note that there are some crimes which are graded as a summary offense for the first violation but as a misdemeanor for a second violation and a felony for all subsequent violations. The fact that you were charged with a summary offense last time does not mean that this charge will be a summary offense.
For more information, you'll need to have a discussion with a local criminal defense attorney.
This answer does not constitute legal advice and does not establish an attorney-client relationship.