Is your laptop screen very dim? Can you only just make out an image? Don't worry, chances are your problem can be fixed without needing to fork out on a new laptop.
There are several possible reasons for a screen not to illuminate, the most common being a fault with the inverter or the backlight. There are a few other less likely causes such as a damaged or fault inverter cable, the screen itself may be faulty or even the laptop motherboard.
There are a few checks you can do to try and determine which component is at fault:
- Make sure that your laptop is set to display the internal screen (as opposed to an external monitor). The usual way to toggle between the two is to hold down the FN key and press either F4 or F5 (completely depends on your laptop, look for the monitor icon on the key). If when you do this the laptop screen flashes chances are the inverter is trying to start the backlight which points towards either a fault with the backlight or the inverter itself.
- The lid switch which turns the display off when the lid is shut may be jammed down causing the screen to be turned off, it's always worth checking this for a quick and easy fix.
- Another option is to reset the BIOS and revert to the default display settings, a faulty CMOS battery can be the cause of these settings being messed up.
Other than the above checks, the only other method of finding the fault is by substituting each likely component until the problem is solved. There is a range of Laptop Inverters and Laptop Screens available on eBay for various makes and models.
Unfortunately Inverters can only be repaired by a qualified electronics engineer due to the complexity of the component, the only other option is to replace it with a used inverter that is tested working by the supplier.
To test the Backlight you can connect it to a working inverter. If the screen lights up then that confirms that the backlight is fully working and the fault is elsewhere.
Warning: Be careful when testing a backlight as they can give off a substantial shock and can be fatal if you have a weak heart.
Do a detailed check of the LCD Cable making sure that none of the wires have broke and the connectors are all secure. There are also many Screen Cables on eBay should it need replacing.
For the inverter to do it's job it relies on the motherboard telling it when to turn the backlight on and off. When the motherboard has a fault it is possible for it not to send a signal to the inverter which results in the screen not being illuminated. If you have already eliminated the previous components mentioned above then the motherboard is often the cause of the problem. If your inverter, backlight and screen cable is tested working, have a look for a replacement Motherboard for you laptop.
If you have eliminated all of the previous components and tested that they are working then it is possible that the screen itself is faulty. This is uncommon but it can happen and is the only real possibility if you have 100% confirmed that the other components are working. Fortunately, you can also purchase fully tested Laptop Screens from reputable suppliers.
Thanks for reading this guide and I hope it helps you in getting your Laptop back to working condition. Enjoy!
Disclaimer: This guide is made purely to give advice to anyone looking to repair a fault with their laptop.We accept no responsibility for any loss or damage to any components by following this guide or not.