Model A1502 / 2.4, 2.6, or 2.8 GHz dual-core Intel processor / Released October 2013

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No backlight, but display is working fine.

Hi all,

Please help me to get this backlight issue fixed.

Yesterday i was cleaning my MBP 13" retina A1502 model and unfortunately i forgot to remove the battery power. While the board still in power ,i accidentally removed the Display flex cable. After i assembled the Display the backlight is not coming UP, Apple logo on back lid is also not lighting, but when i flash a bright light on display i could still see the login page barely. seems everything else working fine, only backlight is not coming UP.

please help me to get it fixed , as the apple is demanding for board replacement which is much expensive for me to spend, also i lost my warranty just 3 months back.

Any help would be much appreciated , thanks

Answered! View the answer I have this problem too

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Use compressed air to blow out the connector carefully and try to look in side the connector with a magnify glass see if you seen any damage, you should see black with rows of gold pins not touching each other. Check the cable too for burn marks or debris and also the components around the displayport itself.

Is your keyboard backlight on ? Also next time start holding CMD+Option+P+R

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Thanks John, I will use a blower to clean the socket and cable pins. yes , the keyboard backlight is working fine. But i figured out one thing that the display cable at logic board connector side has a tiny plastic edge is broken on right end side and the right-last pin i guess pin 30 seems hanging on without plastic guard. but still able to put into the connector without problem. Will this make any short in display electronics or would be fine? becox i still see the display showing login page without backlight. i also tried the CMD+Option+P+R but no change.

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Also FYI...i can able to work on external display through HDMI port with no issues. I see other posts saying F7700 fuse may be damaged.. should i look into that directly or it can be solved without replace the fuse .. pls help ~~~

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You could start with checking fuse see this answer

Where is the location of the back light fuse 820-3476-a?

I would need to see a picture of the display port connector before I commented on the corner part it's possible it could have caused short.

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Hi john, I checked the connector there is no short. I only read 4.5 volt on pin 1 display cable., pls help me to locate L8300 so I can check voltage level also how to check if the lcd display driver chip is ok or not what voltage I should read and pin diagram for that chip. Can I check F7700 fuse status while stil soldered on board, pls help my backlight is not light up after I removed the display cable while still system ON. Sorry !! pls help

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I would go back through and make sure you've got every cable plugged in to the correct connector and none are bent into a odd shape or pinched. That will cause big problems. Also try doing a hard reset

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Also, make sure you haven't over tighten anything, I've done that before and got that same problem from that.

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LOL that's what I said... I just went into a little more detail to inspect everything.

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Hi Gary, thanks.. i believe i didn't have over tighten any cable.. i just see that while i removed the cable unknowingly a plastic protective of Right-last pin of logic board side cable ,a tiny plastic part is broken away , but the last gold pin is still there and able to put into the display connector without issue, also the display is showing login page while turn on.. but NO backlight. should i need to change the backlight fuse F7700 as i read it in other posts. thanks for your suggestion further !!

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Selvam,

You might try and find someone a little better at the diagnosing those type of issues. I am a rookie, not that good to know about those type of issues.

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