Abstract: A vehicle antitheft system includes a MOSFET (418) with associated power and logic circuitry that can be housed within a starter solenoid housing (704) for preventing control current from activating the solenoid unless an authorized enable signal is received. The enable signal can be transmitted by a hand-held rf transmitter. In alternate embodiments, the MOSFET can be disposed in a housing separate from the solenoid and mounted near the solenoid, and the MOSFET can be controlled by an rf-generated enable signal or by an impulse-generated enable signal. In the latter case, the MOSFET is activated to close the solenoid control current circuit path only when a single impulse signal, e.g., from a door latch lock, is activated. If two impulse signals are received, one from, e.g., the door latch lock and another from, e.g.