If you ever plan on traveling to Downtown Los Angeles on the 110 Freeway I would suggest buying one of these Fast Trak transponders to avoid the fine. The initial notice fine will include a $25 penalty. If the notice is not paid within 30 days, an additional delinquent penalty of $30 will be assessed. These transponders can be picked up an any AAA office or at an Albertson store.
The 110 Freeway is no longer free for carpool travelers and if you don't have a Fast Trak you will get a big fine. I think Fast Track needs to do a better job of informing drivers in the media and local papers of the change. The 110 has been a carpool lane for almost a decade.
Toll violations are civil infractions. They do not affect your driving record, but the California Vehicle Code does permit the withholding of vehicle registration, civil judgments and other collection actions as provided by law. The Metro ExpressLanes first action is to attach delinquent penalties to the associated vehicle registration. If a vehicle registration attachment is not successful, balances are forwarded to a collection agency.