What you need:

From the information that you have provided, it seems likely to us that your laptop screen inverter has failed. This is the most common cause of Inverter powered CCFL laptop screens becoming dim and never backlighting again.

The inverter will be sitting under your laptop screen and look similar to the example power inverter image to the left.

Please note that we do not take responsibility for the diagnostics made with this troubleshooting tool, if you are unsure please seek professional advice.

Isolate the problem:

If the laptop has been involved in some kind of impact, (such as being dropped), or any other kind of shock, it is a sensible idea to ensure the problem is related only to the LCD screen itself.

Connect an external monitor to your laptop and test the machines keyboard, hard disk drive and CD/DVD drives. If all looks and sounds okay it is more than likely that the problem is related only to the laptop screen itself.

Testing or repairing the Inverter: 

Power inverters operate at very high voltages, please ensure the battery and power are both removed from the laptop before you attempt to handle this component.

Because the cost of a replacement inverter is usually very low, most people do not go to the effort of repairing inverters. This does not mean of course that repair is not possible. The most common cause of inverter failure is a failed coil (in orange to the right hand side on the example image above).

The inverter can be tested using a high power multimetre that is capable of handing large voltages in excess of 1000VAC. From the right hand side the two pins of the connector that supplies the laptop screen backlight with power should read 700-1200 volts AC.

The coil can be removed and replaced with another identical coil, for this you will need a fine point soldering iron, a replacement inverter coil and some patience.

We recommend replacing the inverter.

How to find a replacement laptop screen inverter:

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