LID Angle LCD Sensor LAS Cable (Sleep/Wakeup) - 821-04218 - A2491, A3114

The MacBook's Lid Angle Sensor (LAS) is a small, flexible cable containing a Hall effect sensor that detects the exact angle of the screen relative to the keyboard platform. It controls sleep/wake, screen brightness, and security features such as muting the microphone when the screen is closed. The sensor is unique and paired with each screen. When replacing the screen, or if the LAS is damaged, it is necessary to replace the LAS and use a specialized calibration tool.