This board has thoroughly kicked my ass. I'm pretty comfortable with this type of issue, but this one I fear may have a CPU issue...
1. No video, no backlight. I do think the board had liquid at some point based on the eDP connector, but it must have been minor because no corrosion on any caps or anything.
2. 5v at L8300 for about 6 seconds, then it goes straight to 0v
3. Boots to external just fine; when I view displays in system prefs, nothing shows except the external display.
4. Diode on my eDP connector all match a working board. Voltages don't of course.
5. SMC_LID is high (3.3v)
6. Known-good 2015 display; tested with 2 other boards, display is definitely working fine.
7. Didn't find any shorts on 5v_s3, 5v_s0 or anything.
When I do have 5v on L8300, there's no LCD activity at all, not even briefly. No panel shifting or data of any kind. Replaced U8300 and U8330 out of frustration because they do resolve a ton of these backlight/video issues, but no change at all. Replaced eDP connector because it had scaling from the board being cleaned, and it didn't look "perfect" (not damaged, but not A+).
Any help or direction appreciated...this one has me baffled.
1. No video, no backlight. I do think the board had liquid at some point based on the eDP connector, but it must have been minor because no corrosion on any caps or anything.
2. 5v at L8300 for about 6 seconds, then it goes straight to 0v
3. Boots to external just fine; when I view displays in system prefs, nothing shows except the external display.
4. Diode on my eDP connector all match a working board. Voltages don't of course.
5. SMC_LID is high (3.3v)
6. Known-good 2015 display; tested with 2 other boards, display is definitely working fine.
7. Didn't find any shorts on 5v_s3, 5v_s0 or anything.
When I do have 5v on L8300, there's no LCD activity at all, not even briefly. No panel shifting or data of any kind. Replaced U8300 and U8330 out of frustration because they do resolve a ton of these backlight/video issues, but no change at all. Replaced eDP connector because it had scaling from the board being cleaned, and it didn't look "perfect" (not damaged, but not A+).
Any help or direction appreciated...this one has me baffled.
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