1 Display flickering, backlight issue and coil whine noise
Hi there, hope you are fine.
I have a MacBook Pro Mid 2012 13" A1278.
(Core i5 2.5Ghz). I bought it from ebay. About a month ago, I upgraded the RAMS and SSD. Also putted some new thermal paste on the processor.
While putting everything back to place, I bend one pin of the LVDS cable. I flattened it and put back to the socket. It was working fine.
Yesterday all on a sudden I saw my Laptop had grey screen while booting up. Then I moved the screen lid a bit, then display came. I thought something was happening with the LVDS cable. Then I removed the back cover once again and saw there is some dust on the LVDS cable and socket. I gently cleaned it with Isopropyl alcohol. After one hour, I started my laptop, and it started buzzing.
If I press the button to increse the brightness, a coil whine noise is happening. The display shows video, but the backlight flickers. A hissing noise is coming from my laptop. Previously there was nothing like that.
Can you help me please?
What can be the issue with my laptop? The LVDS cable? Or the display assembly? Or the logicboard is ruined?
I am a student, and I don’t have another computer at the moment. I am very much upset and worried. Please tell me how can I fix this issue.
Update (05/07/2020)
I wanted to take a second chance. Two days ago, I opened it up again, cleaned the LVDS connector and LVDS cable pins with Isopropyl Alcohol, and a toothbrush.
Previously the display was black. Now the display came. It’s working well with full brightness. No glitches, no flickering.
But when I try to reduce the brightness, it makes a high pitched hissing noise. And also the display shakes a little bit. Other than that, with 100% brightness, it’s fine.
In my opinion, maybe it’s a hardware issue, or maybe the LVDS cable is faulty. Or it can be a issue from some tiny small components of the logic board, or anything, I don’t know.
Now, my question is, do I need to worry about it?
Update (07/19/2020)
There’s no visible damage in the LVDS cable or connector. But the LVDS cable's left pin was slightly bend while removing for the first time; then I straightened it and put it back to the connector. It was working fine. Suddenly the whine occurred with the brightness up-down. Here's a audio file- https://drive.google.com/file/d/1RKdJl6F...
Is there any other chip or components that can cause whine with the display?
What I want to ask, do I really need to care or bother about it? Or should I just leave it like that?
Do I need to replace the LVDS or the connector or both?
Other than that, the computer is working fine. Just I have to use it with full brightness.
Is this a good question?
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5 Comments
Hard to say what is the cause of the whine. Typically coils whine as they age, so that could be the issue. A bad connection can also cause a whine. Hope about posting a picture or two of your LVDS cable focusing on where you damaged it.
by Dan
@danj
Thanks for your reply, Sir. The damage is not visible. But the LVDS cable's left pin was slightly bend while removing for the first time; then I straightened it and put it back to the connector. It was working fine. Suddenly the whine occurred with the brightness up-down.
Is there any other chip or components that can cause whine with the display?
What I want to ask, do I really need to care or bother about it? Or should I just leave it like that?
What's your sugestion? Try replacing the LVDS or the connector or both?
by Tawsif Munawar
Can you post a sound file or vid so we can hear it.
by Dan
@danj Sure, here's a audio file- https://drive.google.com/file/d/1RKdJl6F...
by Tawsif Munawar
@danj Did you hear the noise Sir?
Other than that, the computer is working fine. Just I have to use it with full brightness.
Do I need the worry about it?
by Tawsif Munawar