Dykstra entered his plea Wednesday in a Los Angeles courtroom to one count each of assault with a deadly weapon and lewd conduct. He also received three years' probation.
Prosecutors say Dykstra exposed himself to several women who responded to ads for personal assistants and housekeepers. During one incident, prosecutors say, Dykstra held a knife and forced the woman to give him a massage.
In March, Dykstra was sentenced to three years in prison after pleading no contest to grand theft auto and providing a false financial statement. He is currently awaiting trial on federal bankruptcy charges.