Amanda Bynes has reportedly "gone off the grid" following her misdemeanour hit-and-run charges.

The troubled actress may spend up to one year in jail, six months for each count, should she be found guilty of the crimes.

In April Amanda was accused of hitting a vehicle in a rental car while driving on the 101 Hollywood Freeway and then fleeing the scene. This case was dropped then reopened when she was accused of a second hit-and-run on August 4.

Although her driver's licence is suspended, Amanda was photographed Tuesday operating a vehicle illegally in Los Angeles and possibly smoking marijuana behind the wheel.

"Amanda's completely gone off the grid. She won't speak with her manager, her agent, her publicist; she's not returning anybody's phone calls," a friend revealed to Radar Online.

"She seems to be having some serious mental health issues and she's always out of it. She really doesn't seem to be in touch with reality."

Amanda apparently doesn't believe that she needs help.

"Amanda is refusing to go to rehab or seek any form of psychiatric treatment or diagnosis, because it's clear something is up with her," the source revealed.

"She's a lost little girl right now."