If PennDOT finds that you've been driving your vehicle while it's been uninsured, your license will be suspended for

Under Pennsylvania law, every driver must maintain vehicle liability insurance on his or her registered motor vehicles at all times. If PennDOT finds that your vehicle was not insured for 31 days or longer, your registration will be suspended for three months. Furthermore, if PennDOT finds that you drove the uninsured vehicle, your driver's license will also be suspended for three months. [Driving Without Insurance; The Pennsylvania Point System; Chapter 4: Driving Record Information; Pennsylvania Driver's Manual]