Thank you for the reply. I'm sorry for the delay but I'd turned in for the evening before you responded.
In New Jersey, drugs containing a low concentration of codeine are schedule V drugs. Possession of schedule V drugs is an indictable offense in New Jersey. Specifically, it would be a crime in the 4th degree, which has a maximum possible sentence of 18 months in prison and/or a fine of up to $15,000.
The police don't need much evidence to stop a car. An "articulable suspicion" -- somethng more than just a hunch but less than probable cause -- will do. If the car's license plate was partially obstructed, which is to say, covered by something so it could not be read, that would give the police a valid reason to stop the car, ask for the driver's ID and yours as well.
They can also make both of you exit the car and pat you down for their safety. They can take any contraband in plain view in the car. But if it comes to searching the car or of searching your bag, they need probable cause -- a reasonable belief that you're engaged in criminal activity -- and either a search warrant or an exception to the warrant requirement, such as your consent. So there may be a problem with this search which could be helpful down the road if you want to fight this case.
Do you have a prescription at home for the Tylenol 3 that would predate the search and seizure? If so, with a lawyer, you may be able to get this case dismissed. If not, typically, if you wanted to resolve this case without taking it to trial, you are looking at nothing worse than probation. Also since this is the lowest level indictable offense in New Jersey and there are only two pills, the prosecutor may be willing to reduce this to a disorderly person's offense which, under NJ law is not considered a crime, or offer you a diversion type of disposition where you essentially work off your conviction by staying out of trouble during a period of supervision, paying fines, doing community service and taking anti-drug classes. When you complete your obligations successfully, your case gets dismissed.
So even though the worst case scenario is not a good one, there may be problems with the State's case which could result in a favorable disposition for you. All the same, you should have a lawyer with you on your court date to assist you in fighting these charges. It is possible that you can come out of this one without being convicted of a crime, but since that may have to be negotiated and because criminal cases can have lifetime negative repercussions, don't try to handle this on your own.