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    820-00840-A not starting

    Hi, I have this 820-00840-A board with liquid damage around U7650 and the backlight stuff also. I've narrowed it down to U7650 not creating PP5V_S5 and that's due to PMIC_EN_P3V3S5 missing. So, checking around PMIC, I could see that PP3V1_RTC is good, PP3V3_LDO3V is good, PP1V25_VREF is good...
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    820-00840-A 20V 44mA

    Hi, I have this board that have signs of liquid spill. It won't turn on. CD3215 stuff works fine, I get 20V on the charger, so I have good PP3V3_G3H and PPBUS_G3H is present also. But then I get no other rails, no S5, S4 and probably nothing else either. The enable signal for those rails all...
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    Touchpad won't click

    Hi, I'm not quite sure if this is a logic board issue, but since it may, I'm asking anyway. I got a 15-inch touchbar macbook pro with no keyboard and no touchpad. Knowing that keyboard goes into the touchpad, I immediately suspected the touchpad or its ribbon cable. The cable got replaced but...
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    820-00923-A not turning on - 20V 180mA on the charger

    Hi, I have this board from an A1706 which is not turning on. I do get 20V from the charger. Checking power rails and big coils on the board, I can see that I'm not getting PP5V_S4_T_USBC and PP5V_S4_X_USBC (enable signal is driven low by CD3215s) Also PPVCCEDRAM_S0_CPU is not present (created...
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    820-00840-A Backlight issue

    Hi, I'm stuggling with this board. I got the board from a laptop which had obviously been taken apart previously. At first, I only got 5V on the charger, so I replaced one of the CD3215s (the one that got hot) and then I got 20V and the board was booting fine. Except there was no backlight...
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    820-00840 not turning on

    Hi, I have a board from an A1708 which doesn't turn on. No trace of liquid spill. At first, plugging in the charger gave me 5V only, and around 150mA of current draw. I figured out that my first issue was that it was missing PP3V3_G3H, and that was due to a short to ground (approx 2 Ohms) I was...
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    820-00840-A no keyboard, no trackpad

    Hi, This is an A1708 and somebody has stepped on the keyboard. The topcase is therefore bent downwards in the middle of the keyboard. Luckily, it didn't seem to bend the logic board itself. I was able to unscrew it and it didn't pop out or anything like that. I got a new topcase, but still don't...
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    820-00239-A SSD issue

    Hi, I have this board that gives me a question mark folder. Booting an OSX installer from USB shows no internal storage in Disk Utility. Booting an OSX installed on a USB drive gives me a critical firmware update issue. Also, the touchbar doesn't work, which I believe is normal as the T1 chip...
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    820-3536-A with a half-shorted PP3V3_S0

    Hi, I've got this board and it's giving me trouble. It will not start because PP3V3_S0 only has 1.8V When I measure resistance to ground, I get about 130 Ohms, while a good board has approx 1KOhm Thing is 130 Ohms is too much to be able to get the bad guy to get hot enough to find it. I've...
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    A2159 display compatibility

    Hi, I've got a display that comes from a dead A2159 and I don't have another machine of that kind to test it. Physically it looks similar to the display of an A1708. Are they compatible parts ? Can I put it in an A1708 in order to test it ? And then, for the sake of completeness, same question...
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    820-00923-A stuck at 5V

    Hi, I got a liquid damaged board that doesn't manage to get 20V from the charger. From the corroded areas, it is pretty clear to me that the top left CD3215 (UB400) is, among all 4, the one that's causing trouble. Another hint is that I get power loop on 3 of the ports, and on the last one, I...
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    820-00840-A not turning on

    Hi, I am practising with another 820-00840-A board that does not turn on. There is no sign of liquid damage. My charger gives 20V so I have PPBUS_G3H. PP3V3_G3H gives me 3.41V Then my S5 rails are all missing. I figured that PP3V3_S5 reads 7 Ohms to ground. I suppose this means a short to...
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    A1708 820-0084-A missing PPBUS_G3H

    Hi, I have acquired a liquid damaged A1708, for practicing purpose. I am certain this laptop has never been touched, there has been no prior attempt to repair it as I know the previous owner who is responsible for the spill. The CD3215s look fine as my charger goes to 20V, however the board only...
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    A1502 EFI serial number issue

    Hi, I have an A1502 here which came in with a backlight issue. Lots of corrosion all over the board edge near the hinges, which affected the display connector as well as the EFI ROM area. I got backlight issue sorted out and the laptop now works just fine, except for one thing. It reports...
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    820-3437-B fan spins, ramps up to high speed, no display/backlight

    Hi, I was given a not working MBA in which coffee has been spilled. First inspection revealed a bit of corrosion next to U7200. I cleaned that, and replaced the caps and resistors involved. The rest of the board has traces of coffee, but nothing too bad and no other trace of corrosion. I cleaned...
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    820-476-A no fan spin

    Hello, So, this is my first attempt at an Apple board repair. I have a defective board taken from an A1502 2013 13' Retina MBP. No sign of liquid damage, no obviously burnt component. Overall board visually looks in very good shape. Board gives a green and then orange light on the charger, but...
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