* Neutral Safety Switch (NSS): This switch is crucial. It's connected to the transmission and prevents the starter from engaging unless the gear selector is in Park or Neutral. While it doesn't directly *release* the park pawl, it's a major player in the overall system, preventing the engine from starting if it is not in park or neutral.
* Shift Lever Position Sensor: This sensor, often integrated into the shifter mechanism, constantly monitors the position of the gear selector. It tells the PCM (Powertrain Control Module) where the lever is.
* Park/Neutral Position Switch (PNPS): Similar to the NSS, but more specifically indicates whether the transmission is in Park or Neutral.
* Brake Pedal Switch: This switch is essential. The vehicle will not allow the shifter to be released from Park unless the brake pedal is depressed.
* PCM (Powertrain Control Module): The PCM receives signals from all these components and controls the shift interlock solenoid (or similar mechanism). It is the brains of the operation, making the final decision based on the inputs received.
* Shift Interlock Solenoid/Mechanism: This is the actual component that mechanically releases the park pawl, allowing the shifter to move out of Park. The PCM activates this solenoid only when all the other conditions (brake pedal pressed, correct gear selector position signals) are met.
Therefore, there isn't one single "switch" that controls the release, but rather a sophisticated system working in concert. A fault in *any* of these components can prevent the shifter from being released from Park.
