Depending on the system model Dell systems have diagnostics indicators that helps us identify the point of failure. So that I can suggest you how identify the point of failure please reply with the exact system model number of your Dell laptop. Below mentioned are some of the basic troubleshooting steps for you to try and check if these steps fix the problem or help you isolate the issue:
1. Remove all external peripherals.
2. Disconnect AC adapter and power cord.
3. Press and hold the power button for 10-15 seconds to drain flea power.
4. Power on the computer and check if it starts to work.
5. If the computer doesn't power on normally in the above step, observe if the computer emits any beeps or any pattern is displayed by the LEDs on the machine.
6. Check the status of the light on AC Adapter when plugged into the machine.
The steps indicated above will help you isolate the problem, please reply with the exact symptoms exhibited.
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