I have a Dell Latitude D630 laptop PC. For a while, the backlight screen was fluttering. It would get darker in some spots and get lighter in other spots. Now, when I boot it, it quickly flashes the Dell logo then goes dark. When I place a bright flashlight against the screen I can barely see the image. Is it the backlighting bulb (or bulbs) or the inverter? Is there a way I could troubleshoot to make that determination?

 

You can replace the inverter ,test it with a multimeter to see if it's giving any output voltage, or if its getting a supply, It's located in the screen lid.

 

You can replace the inverter ,test it with a multimeter to see if it's giving any output voltage, or if its getting a supply, It's located in the screen lid.

I disconnected the output of the inverter from the display panel and measured its output voltage. With a digital multimeter set to AC volts, its output was erratic. It was fluctuating between 10 and 200 volts. With an analog meter, the needle was steady at 20 volts. Do you know what the output voltage should be?