no backlight – macbook pro retina

so, i get this call about an apple macbook pro retina. a backlight issue. – a tech friend’s cat had dumped the computer and cracked the screen. owner is pretty tech savvy, and purchased the screen and did the change himself. but in the process, the display would not light up. so i get the call.

now these retina screens are picky, and need to be for the year it was made. even though they look similar and fit properly, a different year model will not light up. so the first thing we did was to identify his device and check to make sure he had ordered the correct year. and yes, he did. 2012-2013.

sometimes parts can arrive defective, so next we tested the computer with a known good screen and it still did not light up. which leads us to some sort of board repair revolving around the backlight.

keep in mind that there are two different types of issues when you are not able to see your screen. even though the backlight may be out, you should still be able to see the display faintly. sometimes it’s more pronounced when an external light source is used. it is possible that the backlight is out as well as the display. two separate, but related issues.

this device is the macbook pro retina model a1425 board # 820-3462-a

my initial hope is that this is just the fuse and after looking at the schematics we find and locate the fuse that is responsible for the backlight.

backlight schematic

boardview

then to test for continuity. and sure enough, no beep.

so, lets remove that filter and put a new one on.

heat shielding

the filter is located right next to a plastic clip connector that connects the keyboard to the motherboard. this thing can easily melt and since we are going to be applying a significant amount of hot air, i want to make sure this doesn’t melt. so i use a combination of the pink heat shield with they yellow kapton tape.  personally – i don’t like to take any chances, so i further mask with some silicon and fiberglass. not sure if that is helping or hurting as my air nozzle is quite small already, so am i helping to deflect the heat? or just keeping it under wraps beneath the fiberglass and silicon? hmmm. if you have any comments, leave a message below.

silicon and fiberglass

the filter was kind of attached – burnt in i would say, but finally got if lifted an the new one properly in place. as you can see, the pink goo turns crusty, deflecting the intense heat away from what is underneath. this can then be peeled away and hopefully, it has protected the parts we did not want exposed to this heat.

crusty pink heat shield

so we clean it up and then test again. and as you can see, the surrounding areas were unaffected.

cleaned work area

now keep in mind, the settings i use for this are around 380C / 700F and that tiny filter is very close by. not a bit of warping or melt. a nice clean job.

closer look of the backlight fuse

one more test before assembly to make sure the filter is still good.

and now to turn it on – and yes! i don’t have to dig any deeper!

apple logo

success!

fully functional retina macbook pro – feels good.

thanks for joining me on some of my repairs.

if you have an issue with your device, and you are looking for an experienced tech to take a look at it, please contact me with a description of your device and it’s symptoms.

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