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Hi - I have an A1502 with a bad backlight (flashlight test shows the display is working.) How can I diagnose whether the problem is with the logic board or the display before purchasing and swapping in either? Extra detail: the backlight did not completely die all at once. It stopped working, then came back on a few days later, went out again, and repeated this cycle for a week or two before finally turning off for good. Update (06/09/2020) Here are some pics - and the backlight is currently back on.
You’ll need to pop the bottom off and inspect the display cable and its connector on the logic board. Follow this guide to Step 6 MacBook Pro 13" Retina Display Late 2013 Display Assembly Replacement then jump down to Step 11. Hold the cable like its held in the 3rd image taking a nice clear closeup of the connector and the cable end and post it here for us to see Adding images to an existing question
