XPS 8910 Service Manual

Steps to confirm that power-supply unit is defective

1. Disconnect the power cord from the power-supply unit.
   CAUTION: Ensure that you take adequate safety precautions before accessing the components on your computer. See the removing and replacing instructions in the service manual for procedure to access the power-supply unit and its cables.
2. Disconnect the power-supply unit cables from the system board.
3. Connect the power cord to the power-supply unit.
   • If the LED is on for 3 seconds and turns off, it indicates that the power-supply unit is functional. Continue with troubleshooting steps for other devices.
   • If the LED does not turn on, it indicates a power-supply unit failure. Replace the power-supply unit only.