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    820-00138 I/O board USB problem

    This one is really strange. I got A1398 which is working perfectly fine except right side USB port, which is working partially - it recognises external flash drives, USB mouses or even boots and works from external drive OS, but the problem is, that it doesn't recognise iPhone at all. AMP meter...
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    820-00165 pulsing twice

    I'm working on 820-00165 board, which came to me completely dead. After inspection I found out: - small corrosion between C7400 /C7425 and C2951/C2952 - PP3V3_S4 was completely shorted to ground, but it was caused by damaged U8000 (no corrosion around). I've replaced caps and U8000. Now...
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    820-00165 no PP5V_S4RS3 and PP3V3_SUS

    I'm working on 820-00165 board, which came to me with description: "Turned off by itself, after a while turned on, but SSD wasn't detected. Now has no reaction for charger". My observations: - board is clean, no corrosion, no water damage, no mechanical damage. - there is no green light when...
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    820-00850 5v no power, PPBUS_G3H shorted, no PP3v3_G3H

    I'm working on 820-00850 board, it has no signs of liquid or physical damage. Customer states computer just turned off by itself. Some info about board: - Stuck at 5v 0,45A - LDO's on CD3215 are not shorted - PPBUS_G3H is 0V, shorted to groud on system side (diode mode 0,000V) - PPBUS_HS_CPU...
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    820-00840 brain dead

    I'm working on 820-00840 board which got damaged by coffee spill. It had corrossion around U3700/U3770/U2890/U3900/R5640/U8210 (pictures attached). I have cleaned it up, replaced U3770 and U2890, repaired broken traces, replaced damaged resistors/caps. Also resoldered U3700 and U8210. Area of...
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    820-00597-A iMac 21,5" 2017 random restarts, problem with booting to OS

    More than one week ago my customer brought in an iMac 21,5" 2017 for SSD upgrade. I've replaced HDD, cloned all data to new SSD and put everything back together, standard procedure. After few days customer informed me, that computer restarts randomly and then has problem to turn on showing...
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    820-00165 restarting randomly

    I have 820-00165 board on my bench which is restarting randomly, showing "Your computer restarted because of a problem..." message. Board was water damaged in the past, cleaned by other shop. Now it has no signs of corossion or damaged components, looks fine. It starts, sometimes boots to the...
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    820-00609 short on PPBUS / CPU PHASE

    Hi! Today my customer brought in an iMac 27” 5K 2017. As he say, computer turned off by itself and caused all electricity at home to shut down. He felt burnt component smell. I took out the board and found burnt and swollen area on PCB under one of the CPU phase mosfets (Photos of the board in...
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    820-3115 turns on but no post, no chime, no video

    I'm working on 820-3115 board which as customer claims stopped working suddenly. I've inspected it very closely, there is no physical or liquid damage. With battery disconnected and only charger connected it has green light, but it doesn't switch to orange. With battery connected it shows green...
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    Need clean EFI dump for 820-2375

    I got water damaged 820-2375 and the only thing left for me to repair is EFI chip which has pads eaten away, so I can't even read it to write dump to new chip. I have already searched on our forum and internet, but haven't found anything. Can I ask you to share clean dump for this board? It's...
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    Clean EFI dump for 820-00426 board

    Hi, I got 820-00426 board for repair with missing EFI chip and ripped all traces under it. I have tried two dumps I had, computer works on them but very slowly with fans running on max speed. I've tried cleaning ME Region, but it doesn't change anything. Can I ask you to share celan EFI for this...
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    820-00165 not starting, all S0 rails pulsing

    I'm working on 820-00165 which as customer says has died after plugging headphones to the jack. He turned it on after that, but computer went off while loading system. Board is perfectly clean, no corrosion, no liquid, no burnt components. After plugging charger in, there is green and orange...
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    820-00239 works only with keyboard disconnected

    I have 820-00239 board which is working perfectly only with keyboard flex disconnected. Customer says, that computer was dropped. In most cases when I plug keyboard flex in (J4500) computer starts, shows Apple logo, loads system halfway and shuts down. Sometimes it lets me to write password, I...
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    820-3209 keeps burning current sensing resistors

    Hi, stubborn board again. So I got it with not turning on problem. No liquid damage, but had replaced backlight IC before, the rest looks good. There is green and orange light on MagSafe, but fan doesn’t spin, just try to start and stops (Quarter fan spin). PPBUS_G3H ~4v, not shorted. I‘ve...
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    A1398 820-3787 boots with disorted image on screen

    Hi, I'm working on 820-3787 which has problem with disorted image on internal screen. First, when customer came in image was OK. The only problem was that it wasn't passing login screen or was turning off while loading system. I thought it's typical VCORE problem. After one day laying on shelf...
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    A1708 820-00840 no PPBUS, no short

    As it's my first post on this forum I want to say hello to all members! I'm fighting with a kind of odd case of A1708, board number 820-00840. Board looks perfectly clean, untouched, no water signs, no damages, even no dust on it. Customer claims, that computer just turned off by itself and...
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