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Processeur quad-core Intel Core i7 à 2,0 GHz, 2,3 GHz ou 2,6 GHz (Turbo Boost jusqu'à 3,8 GHz) avec 6 Mo de cache L3 partagé.

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Back light not functioning

Cleaned my screen last night. Unfortunately (?), I used eyeglass cleaning spray that I had sitting near by and have used before, although it tends to be thinner and run more than a traditional LCD cleaner. Shortly after, the screen went black. I am afraid some of the cleaner may have slipped below the black clutch cover at the bottom of the display and is shorting the back light strip or even caused a fuse on the board to pop.

I can see my desktop and application windows when shining a light through the apple logo on the back of display. So, obviously the display is getting the video feed, but not being back lit.

External monitors work fine via HDMI. Changed the automatic graphics switching settings to try to determine if the problem is the dedicated GPU. No change or affect. In fact, I can still play games at 60fps or better at high resolutions, so I have a feeling the GPU/logic board is ok.

Attempted the usual NVRAM and SMC reset, but to no avail. Left the display up and the computer powered off overnight, hoping that perhaps the liquid would dissipate if that is what is causing the problem.

Ironically, I also installed a security update yesterday, but that was about 12 hours before the back light went out.

Any help would be greatly appreciated. I am handy with electronic repair, so just need to know where to go from here.

Update (02/01/2018)

I ran Apple Diagnostics and "VFD002" is returned. Not ground-breaking by any means as it tells me what I already know: that something is wrong with the display. Thought I would include this info anyway in case it proved useful in some way.

And one additional update:

I have read that Apple's security update 2018-001 is causing similar problems for others on OS 10.11. However, after I booted from a cloned 10.9.5 drive I still have sitting around, the back light remains off. So, my problem is definitely hardware related.

Fuse pictures:

Block Image

Block Image

Update (03/11/2019)

I have been using the laptop as a desktop since the malfunction and have had no issues other than the battery swelling up, requiring replacement. But since I am a stubborn man, I am going to try to fix it.

I already own a dissecting scope and have acquired the schematic and boardview file for my board (820-3787-A). I replaced the backlight fuse which was definitely blown. Even with a working donor display, the backlight still wouldn’t turn on. Upon further inspection I noticed a hole in the top of the LED control chip (U7701). Obviously it exploded! So I ordered a hot air rework station and removed the chip. I was going to put the new one on, but noticed some dodgy looking resistors and capacitors. So that leads me to a few new questions based upon the schematic.

  1. Many of the resistors are marked TF. Are those thick film or thin film resistors? Does it matter?
  2. Likewise, there are some resistors marked MF or MF-LF. I am assuming MF = Metal Film. Correct me if I am wrong. What does the MF-LF stand for? Looking on Mouser, etc. I do not see any resistors of that type.
  3. There are several capacitors marked with package size 402-2. I know what a 0402 package is. And I know this is still indicating an 0402 package. But what is the “-2” part of the package? I am assuming a specified height, but once again cannot find an actual package specified as such.
  4. At the top of the schematic page for the backlight circuit I see the following in the page notes: BKLT:ENG - Stuffs 10.2 ohm series R for engineering builds | BKLT:PROD - Stuffs 0 ohm series R for production. Several resistors on the schematic are marked as “BKLT:ENG “ and 10.2 ohm resistance. However, since this is an actual production model, would I replace those with 0 ohm resistors if need be or stick strictly to the schematic designations?

Probably have more questions to come, but those are the most important at the moment. Any help would be greatly appreciated.

Répondre à cette question J'ai le même problème

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I would start by checking this: MacBook Pro Repair Extension Program for Video Issues to see if you can sneak it in. Otherwise see below.

par

I wish that was the case. Apple support indicates that mine is not included since it is a late 2013.

par

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2 solutions

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Sadly, the cleaner dripped into the LCD panel. Here's a good view of the lid assembly: MacBook Pro Retina Display Teardown.

What happened is the surface tension of the liquid wrapped around the edge of the panel on the bottom edge and is now shorting the lines. Even after drying for a few days the damage is likely done.

Time for a new display assembly: Remplacement de l'écran complet du MacBook Pro 15" Retina fin 2013 and the needed part: MacBook Pro 15" Retina (Late 2013-Mid 2014) Display Assembly

Image MacBook Pro 15" Retina (Late 2013-Mid 2014) Display Assembly

Produit

MacBook Pro 15" Retina (Late 2013-Mid 2014) Display Assembly

$549,99

Image MacBook Pro 15" Retina Display Mid 2012

Tutoriel

MacBook Pro Retina Display Teardown

Difficulté :

Modérée

Image MacBook Pro 15" Retina Display Late 2013 Écran complet

Tutoriel

Remplacement de l'écran complet du MacBook Pro 15" Retina fin 2013

Difficulté :

Modérée

1 - 2 hours

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I was hoping you weren't going to say that. As I stated, I know it's getting the actual video feed, just no back lighting. I did open up the case to check the backlight fuse. Unfortunately, I do not have an audible multimeter, but measured 0.3 resistance on the fuse. I also took a couple of pictures because one end of the fuse looked odd - see updated post.

par

The fuse looks fine but thats not always the best way to judge things.

If you have access to the schematics and board layout drawings for your system and had the tools and skills. I'm sure you could test out a few more devices, like the driver logic (WLED or Buck) as they could be damaged as well but you need to start off with the more likely part first.

par

Alas, I have been unable to find the schematic for my board: 820-3547-A.

I have found the boardview for it though.

par

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Click command control power to reset. If that doesn't help click on system preferences go to display and check every thing.

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Are you thinking resetting of the SMC? He already gave that a try.

par

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per4manz sera éternellement reconnaissant.
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