Acer Aspire 5734Z Back light problem repaired
Hi folks! Here is another simple backlight repair guide of the Acer Aspire 5734Z laptop. The customer brought to me this equipment with a problem, randomly no screen if the LCD was lift up. Hmmm I supposed there could be contact problem or have a broken cable wire.
In most of the time the LCD worked well but in some condition the backlight was gone. I opened the front cover of the LCD and searched for the inverter because from there I can follow the wirings from the motherboard to the CCFL tube. The CCFL stand for Cold Cathode Fluorescent Lamp.
After I powered on the laptop I had no luck because there was no display on the LCD. First I powered on my DSO ( Digital Storage Oscilloscope ) and put the probe over the HV transformer, I didn’t touched the transformer, just moved the scope probe in the air over the item. This is how I quickly check if the HV transformer does have some activity. If oscilloscope screen did not appear a sine wave with relative high amplitude then something is wrong.
I saw nothing on the scope. So I decide to stir the cables on the ccfl connector with a tweezers.
Be careful to work on the secondary side of the inverter board. That is the part where the CCFL got the power. On the picture above that is the side where you can see a red and white wire on right side! There could bee 1000 or more voltage !!!
Nothing happened with the moving of the wires. There was still no screen. Then I go to the left side of the inverter, where the power came from the motherboard to the inverter that is the power supply connector on the picture above.
Then I got a flickering backlight on and off situation. I pulled out the connector and inspected if there was a crack maybe or dirty or whatever. I found only a very weak connection in the socket. Maybe that could be the reason for a connection loose. I took a strong duck tape and glued it over the connector after I pulled back the connector into the socket. You can see the black tape on the left side connector on the inverter. Therefore, the connector cannot loose connection.
After a day or so testing the laptop in several mechanical conditions like powering on and off, lifting half the screen, then full, than back to half, closed, and fully opened and so on, the backlight still worked. It was already several days with the owner and he gave me a call saying the laptop was working fine.
This was another easy and cheap repair. You also need to know that there are also some hard to fix cases. I hope you enjoy my article and will be educative for someone.
This article was prepared for you by Christian Robert Adzic from Novi Knezevac-Serbia.
Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments.
P.S- If you enjoyed reading this, click here to subscribe to my blog (free subscription). That way, you’ll never miss a post. You can also forward this website link to your friends and colleagues-thanks!
Note: You can check his previous post in the below link: