Lcd Built-In Self Test (Bist); Wifi Power Cycle; Flea Power Release - Dell Vostro 5515 DVC9Y Service Manual

1. Press and hold both the M key on the keyboard and the power button to initiate M-BIST.
2. With both the M key and the power button held down, the battery indicator LED may exhibit two states:
a. OFF: No fault detected with the system board
b. AMBER: Indicates a problem with the system board

LCD Built-in Self Test (BIST)

Dell laptops have a built-in diagnostic tool that helps you determine if the screen abnormality you are experiencing is an inherent
problem with the LCD (screen) of the Dell laptop or with the video card (GPU) and PC settings.
When you notice screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry image, horizontal or vertical lines,
color fade etc., it is always a good practice to isolate the LCD (screen) by running the Built-In Self Test (BIST).
How to invoke LCD BIST Test
1. Power off the Dell laptop.
2. Disconnect any peripherals that are connected to the laptop. Connect only the AC adapter (charger) to the laptop.
3. Ensure that the LCD (screen) is clean (no dust particles on the surface of the screen).
4. Press and hold D key and Power on the laptop to enter LCD built-in self test (BIST) mode. Continue to hold the D key, until
you see color bars on the LCD (screen).
5. The screen will display multiple color bars and change colors on the entire screen to red, green, and blue.
6. Carefully inspect the screen for abnormalities.
7. Press Esc key to exit.
NOTE: Dell SupportAssist Pre-boot diagnostics upon launch, initiates an LCD BIST first, expecting a user intervention
confirm functionality of the LCD.

WiFi power cycle

If your computer is unable to access the internet due to WiFi connectivity issues a WiFi power cycle procedure may be
performed. The following procedure provides the instructions on how to conduct a WiFi power cycle:
NOTE: Some ISPs (Internet Service Providers) provide a modem/router combo device.
1. Turn off your computer.
2. Turn off the modem.
3. Turn off the wireless router.
4. Wait for 30 seconds.
5. Turn on the wireless router.
6. Turn on the modem.
7. Turn on your computer.

Flea power release

Flea power is the residual static electricity that remains on the computer even after it has been powered off and the battery has
been removed. The following procedure provides the instructions on how to conduct flea power release:
1. Turn off your computer.
2. Disconnect the power adapter from your computer.
3. Press and hold the power button for 15 seconds to drain the flea power.
4. Connect the power adapter to your computer.
5. Turn on your computer.
76 Troubleshooting