Good morning,

Please help me identify an electronic component. The component is in an SOT89-5 package with leads as shown in the photo. It is used on a keyboard board and controls the operation of a specific key row. There are five identical components on the PCB, and whenever I swap one with another, the corresponding key row stops working — so I conclude the component is faulty.

The keyboard is a SteelSeries Apex Pro (US). I cannot find a boardview or schematic online. I have already searched AllTransistors, AllDatasheet, etc., and found several candidate types (voltage...