Follow this procedure to troubleshoot when the notebook power light comes on, HDD activity light activates, but there is no display or very dim LCD.
IMPORTANT: If the LCD is all one color or there are large portions which are all one color, tilt open and then close the LCD screen. If the colors change or return to normal as the LCD is moved or lightly tapped, other than the normal changes in brightness as the angle of viewing changes, the video cable has become crimped in the hinge. The notebook will need service to resolve this issue.  Go to Product Repair.
NOTE: Because each of these steps represents a possible solution to this issue, check the LCD status after completing each step.
- Ensure the brightness of the LCD has not been turned all the way down using Fn+F5 and the arrow keys. The RIGHT ARROW key is used to increase brightness.
- The computer may be in video standby mode. Press any key to activate the display.
- Ensure the AC adapter is properly connected to the computer.
- Ensure the battery pack is fully charged.
- Disconnect any external display, all external devices, and remove all PC Cards.
- Restart the computer.
NOTE: Disconnect the AC adapter and battery pack. Push and hold the power button or slide and hold the power switch, depending on the model, for 30 seconds. This will ensure the computer is completely shutdown before attempting to restart the computer.
- Disable the power management and power option settings to determine if the software configuration is causing the issue.
- Press the Fn+F7 keys to cycle between the video output modes.
- Some computers have an ambient light sensor. If your computer has this feature, turn off the automatic brightness adjustment .
NOTE: Check the manual to determine if your computer has this feature. Manuals are posted on your model support page.
Restart the computer and press the F2 key at the Sony screen to enter the BIOS.
- If the screen is too dark to be viewed, press the F2 key when the startup sound is heard.
- If the LCD is still dark or dim in the BIOS setup, the notebook will require service.
- Reset the BIOS defaults.
- Ensure the RAM memory modules are seated properly.
NOTE: Instructions on accessing the RAM memory modules are included in the user guide. Manuals are posted on your model support page.
If the issue is still unresolved, service may be required.  Go to Product Repair.