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    Anybody tried combing through BIOS dump to see if TouchID (2016/2017) can be re-programmed?

    Just curious if anyone has messed around with combing through BIOS dumps to find any info that might be related to the pairing of the TouchID Buttons. Alternatively, has anyone maybe tried swapping dumps/ME regions between boards to see if the other TouchID would work? Is the TouchID programming...
  2. S

    820-00244 no power

    Have you tried a new USB-C port assembly?...Common for those to fail on this model, and will typically present in the way you're describing. Also make sure your trackpad/cable and battery are both good.
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    820-00281 u9850 keeps shorting

    GPU probably toast.
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    820-00281 change screen now camera not working

    The screens are not need to use an A1707 screen with A1707 boards/units; only use A1990 screen with A1990 boards/units. Probably blew the camera filter near the LCD connector.
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    820-00165 no camera detected

    Check inside the camera connector to make sure no pins are pushed "up" and not making proper contact with the cable; have had a few instances of this. Also, did you buy U3900 reballed, or did you reball it? Where did you buy it? What diode readings do you get at the big coils near the chip?
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    820-00875 No Backlight / No Display

    No, totally incorrect. External display and internal display are handled totally separately. In fact, the eGPU on these boards USUALLY fail with external video working normally but no internal video. I have a stack of 20 boards I'll be happy to show you with the exact issue. Your board is toast.
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    820-00875 No Backlight / No Display

    Don't waste your time--eGPU is dead. You killed it when the LCD cable tore with power applied. I've had a dozen or so boards come in with damaged LCD cables (screwed-through, torn, etc) and it ALWAYS kills the eGPU. You need to replace the board. There is almost no margin of error for working on...
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    820-00281 does not charge. PPBUS_G3H low on battery

    I just remembered something I saw recently, and just to be safe: Make sure you have the battery communication cable right-side-up. Had a customer with similar issues and it turned out he had his battery cable installed upside down...
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    820-00165 HDA_SDOUT/_R Shorted; CPU?

    Working on an 820-00165 2017 that I believe has a CPU fault causing no audio. Checked all the common issues for no audio, but found HDA_SDOUT shorted (.000) at J9500. Since this comes from the CPU, I suspect a CPU fault and nowhere else to go. Removed R1313 and found HDA_SDOUT_R shorted to...
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    820-00840, No Camera, ALS SMBUS fault. SMC?

    I tested it in several assemblies as noted in the original post. It's a board fault, not a camera/assembly fault. With those resistors removed from the board, camera works in all 3 test assemblies of ours. With resistors in place, camera works on none of them. That's why I was suspecting the...
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    820-00840, No Camera, ALS SMBUS fault. SMC?

    No ideas I guess? Will just consider this one fixed with the ALS SMBUS resistors removed. Not ideal having keyboard backlight on full-time and no auto-dim of LCD, but it will work I guess. Thanks.
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    820-00840, No Camera, ALS SMBUS fault. SMC?

    @piernov any ideas on this one? Could SMC fault in such a way that it would only affect ALS SMBUS and not anything else connected to that line?
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    820-00281 does not charge. PPBUS_G3H low on battery

    Inspect areas immediately near USB-C connectors on board. VERY common for people to knock off the diodes/caps when disconnecting the USB-C assembly.
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    820-00840, No Camera, ALS SMBUS fault. SMC?

    Working on an 820-00840 board that had no camera. Tested it in several assemblies as I know the cameras in these panels love to fail. All power lines measured fine around U3900, but I had seen someone about a year back mention the ALS SMBUS sensor causing issues with the camera SMBUS line, so I...
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    820-2796 Kernel panic

    I don't think it's the case in this situation, but you CAN overheat the SPI chip with hot air. This is VERY EASY to do with the Micron N- chips! They will die/damage very easily if you apply too much heat too directly. Usually it just damages/corrupts the BIOS dump itself, but you might see the...
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    820-00850 Can't get past Activation Screen

    That's great to hear! Glad you got it figured out; quite a relief I'm sure. :)
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    820-00850 Can't get past Activation Screen

    Unfortunately restoring the unit won't be possible if it's locked. You can get into DFU and begin the restore process, but it will quickly fail and a padlock will show on your AC2 unit. The locked unit will just boot to a connect-to-wifi screen and eventually get back to the activation lock...
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    820-00850 Can't get past Activation Screen

    Yep this is literally Apple's plan. Forcefully encourage users to log into their iCloud when setting up a T2 unit; enable boot security by default; remove data-recovery lifeboat connector; and make BIOS/SPI inaccessible. You should be able to wipe the unit without the iCloud information; you...
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    820-00850 Can't get past Activation Screen

    Yeah, and having them wipe it via their iCloud account on can be VERY hit or miss. I think it's worked properly maybe...twice...for us. It's always easiest to do it from the unit itself via their login info. Just tell them this is the new reality of board repair; iCloud login info...
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    820-00165 Backlight not working properly on one side

    Thanks so much! If you're interested, and ever got the hankering to whip up a quicker script/method to accomplish that, I'd be happy to compensate you. Just shoot me a message if you ever do!