Screen Issue: No backlight (flashlight reveals content). Fuse? WLed?
- Integrated monitor does not light up
- If I point a flashlight I can see apple logo on startup and log-in succesfully
- HDMI to external monitor works perfect
- It stopped working after the third party HDMI cable broke when the TV did something strange. I guess some kind of discharge. Don't know if it's coincidence though.
- Since that "incident" it stopped working gradually, sometimes integrated screen would come on, sometimes not. Once it came alive while tapping gently the black strip at the back of the macbook, but when I closed it and opened it back again, never came on again.
- Right now the internal screen haven't been on for a while (I'm using external).
- Already did all the special resets (SPM, VRAM, etc.)
- Connectors seem fine: http://imgur.com/a/rU8OL (?)
- This is my logic board: http://imgur.com/a/kVLkY (820-3330-B)
- I'm expecting to understand where's the problem. Identify the FUSE and how to check it, identify the WLED and how to check it. Maybe check the LVDS cable if I'm lucky that's the problem. Have no experience in chipset repair so at least I would like to identify the problem so as not to get ripped off by the technician here in Argentina.
@oldturkey03 the number is 820-3330-B . Is this any help? And please would be nice to know how do I "check" it... I mean, what to do to realise if it's dead or working... Thanx!
UPDATE 1:
I did the continuty test with the multimeter set to Ohm's and it beeped and gave me an oscilating result between 00.2 and 00.4 (originaly is at 1 and quickly goes down).
So, continuity seems OK for the OHM test. This leaves me in an even more intriguing scenario. Maybe the flex cable? Anything else I can test with the multimeter? I have my friend right here with me who is lending it to me for the tests.
UPDATE 2
I unscrewed my monitor completely from the macbook pro and played a little moving the LVDS cable. I left all disconnected but I plugged the LVDS cable and power on the computer...I got light! The screen working perfectly. Then power it off and re-assembly everything to place and again no backlight... but this shows that the backlight itself it's ok. So I guess the problem would be in the LVDS cable? My theory is that when I set it loose it made the connection temporarily? What do you think?
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3 件のコメント
@mauma so I guess this is what you are referring to. No backlight. Correct? I know you said that the LVDS cable and connector are okay, but I still would need you to post some images of it. It will help us to help you. BTW 820-2565 is not your logic board number. That is the Magsafe board. Check for the board number being on the left side of the logic board below the fan. You must have a multimeter to check a few things at least
oldturkey03 さんによる
@oldturkey03
Here are the pics of my logic board: http://imgur.com/a/kVLkY
A friend of mine is lending me his multimeter for this tests but I never used one before that's why I am asking as HOW to check this things : )
The right number for the Logic Board would be 820-3330-B
Thanx for that!
Alex さんによる
Take a look at your LCD cable itself and look for any burn marks or damage. I once chased a backlight issue from IC to IC for 2 hours before I checked the cable and found pins 1 and 3 where fried.
rneeley さんによる