Measure the current-sensing resistor (PR302 or equivalent). It should read a stable 19V against the chassis ground. Short circuits to ground on this rail will instantly trip your bench power supply. Step 3: Always-On Power Rails ( +3.3V_ALW & +5V_ALW )

If you are currently troubleshooting a specific issue on an motherboard, let me know:

The ENE KB9022Q chip coordinates the power-on sequence, keyboard matrix, fan control, and communication with the battery.

Main system input voltage generated from the Type-C charger.

The Intel Skylake-U processor requires several specialized rails.

Identifying the EC (Embedded Controller) signals and BIOS corruptions.

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