Dim Display in laptop (LCD)

There are many reasons responsible for dim display in laptop screen.

Today we will discuss Dim display in LCD only.

First of all find out whether you have LCD or LED screen in your laptop. 

There is simple way out to find out.

All LCD screens come with FL card. you can see it at bottom of screen by removing front panel.

                                               FL inverter card.

If it is not present then it is LED screen. However LED and LCD comes with size difference. We can search in Google by writing our laptop model no and find out configuration details.

Let us discuss Troubleshooting Dim display in LCD.

Check your Screen by replacing another. It is most important to unplug battery from laptop before changing the screen otherwise it causes problem with Motherboard I/O controller.

 If problem is not solved 

Check if following voltages are present on connector of display cable after turning the laptop on) as shown in the image.

19V or 18.5, or 15 (depends upon input voltage)

3.3 Volts on other pin

Also check ground.

 IF 19 VOLTS ARE MISSING..

If you cannot find 19 Volts on connector pins then it is the reason for Dim display.

Now what you have to do is

              

                                                                                                    

You will find 19 Volts at many capacitors or coil on the Laptop Motherboard. Generally 19 V capacitors are big in size or coil same as on inverter card.

Sold a jumper wire from motherboard (where 19 V are present) to any side of coil or +ve side of capacitor as shown in the image. After this you will find 19 volts in inverter card and problem will be solved.

IF 3.3 VOLTS ARE MISSING.

I/O controller Chip in the mother will be responsible for this. You need to change I/O controller chip.

Changing I/O controller will not be easy for fresher. We will discuss it later in other posts.

IF ALL VOLTAGES ARE PRESENT.

IF 19V, 3.3 V, and ground (GND)is present then Change the inverter card. Replacing wrong inverter card may damage motherboard circuit. So it should be same inverter card.

If same inverter card is not available. There is  Universal inverter card also called UFL available in the market at very less price. You can see it in this image

We need to Cut the display cable and remove connector that is inserted into inverter card.

Turn off the laptop and sold these wires to Universal inverter card.

 Sold 19 V wire to power input (V+)

Sold 3.3 V wire to switching signal.

Sold GND wire to ground.

Cover the remaining wires and leave as it is.and plug the connector of screen to other side of inverter card.

Before doing this make sure all these voltages are present on the connector. Use of Universal card is beneficial only if we do not have other inverter card of same model laptop. We will see few videos related to changing I/O controller or using UFL inverter card shortly.

Please note: - This post can be useful for the people who have little experience in this field. May be not easy for fresher.