In the event of a screen inverter failure, the symptoms will be pretty much the same as when the backlight lamp fails. In both instances, the screen stays dark and exhibits only a faint image that can hardly be seen. What you have to realize is that there is only one way to know for sure of the inverter board is indeed defective, and that is by replacing it with an inverter that you know for sure is functioning perfectly. If this fails to show any improvement, you could try out another backlight lamp. This second option is a lot easier, since most laptops typically use the same type of backlight lamp. In fact, as long as you have the right connectors, you could use the same backlight lamp with different inverters.
To get to the inverter board, you will have to check the display panel, which is typically located under the LCD. Many laptop designs allow you to get to the inverter board by removing the screen bezel. Doing so will reveal the inverter’s connectors, which are on either side of the board.
In order to determine if the inverter is drawing current from the motherboard, you will have to use a multimeter. Connect the positive lead to pin1 on the connector and the negative lead to the ground connection, which should be located near the screw hole. Keep in mind that troubleshooting laptop problems that have to do with the inverter can be quite tricky, and you run the risk of a short circuit that could damage the inverter board for good. In the worse case scenario, you may even cause damage to motherboard, which will be a costlier and more difficult problem to fix. So when in doubt, it may be best to have your laptop checked out by a qualified technician.
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