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  1. S

    820-00840 dead after SSD swap

    So you're saying that if PPBUS_G3H shorted to another line in the SSD connector that goes to the CPU, the CPU is probably fried. Makes sense. Ok thank you!
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    820-00840 dead after SSD swap

    Neither machine boots with OR without SSD. No sign of life aside from 20V at USB C meter and main rails OK.
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    820-00840 dead after SSD swap

    So I did a dumb thing. A friend brought me his teen daughter's dead A1708...it was charging (made the tone when USB C charger connected) but no boot chime or video from internal or external displays. Rather than trying to repair it (I just moved offices and am still unpacking my bench, plus the...
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    820-4924 - Did I fry the PCH?

    Thank you, I will do that!
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    820-4924 - Did I fry the PCH?

    Apologies about the re-quoting, I just left the default text in place when I hit the Reply button. Yes my current state is 10ma and no S4 or lower rails. Your initial reply seemed to only be addressing my initial problem with MagSafe, included for context, and you made the jump to that not...
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    820-4924 - Did I fry the PCH?

    Please re-read my post. I got the machine into operating mode but then ran into other issues
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    820-4924 - Did I fry the PCH?

    820-4924 with corrosion around U3220 and U3320, no Magsafe LED or boot. I replaced those ICs and got the unit to boot fine, but without keyboard or trackpad. While testing, I did not have the fan attached. Before I could start troubleshooting the KB/TP issue, I had to go take what I thought was...
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    820-3437 no backlight boost

    I just read the sticky on this topic, sorry for not finding it sooner. I see now why you suggested a PRAM zap...to reset what might have been a fully lowered brightness setting. So I guess I could leave the jumper in place if the owner approves the loss of brightness control. I am curious where...
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    820-3437 no backlight boost

    yes, that gives us backlight with the jumper in place. R7704 tests fine... OK so what does this tell us? BKL_PWN is the source of the problem? Which means I have a CPU issue? I'm assuming I can't leave this jumper in place full time... FWIW with R7704 removed EDP_BKLT_PWM measures 2.1M ohms to...
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    820-3437 no backlight boost

    I've also tried PRAM zap and multiple known-good LCD assemblies
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    820-3437 no backlight boost

    Sorry, yes. I have continuity between pin 5 on D7701 and the boost side of D7701. BKL_EN is 2.85, BKL_PWN is 0.00 (both values are when screen is attached). All resistors measure within spec and traces look good
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    820-3437 no backlight boost

    I have an 820-3437 that had some liquid damage. I have replaced a few components and now have normal behavior (fan-spin, image, proper rails, etc). Only issue is that backlight starts out at about 25V and slowly drops down to the non-boosted voltage as I measure it. I've tried multiple screens...
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    Ultrasonic breaking boards?

    Thanks for the advice John, it was very helpful.
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    apple pricing

    We just facilitated a repair for a client's 2015 13" Retina through Apple Retail. Price was $475, we are located in the Phila, PA market (if that makes a difference)
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    Ultrasonic breaking boards?

    Oh my! I guess I should consider myself lucky with the ones that I DIDN'T have issues with. Thanks so much for the reply. What is a safe oven temperature? I'm assuming a small toaster over will do the trick (as long as it's wide enough for the boards)?
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    Ultrasonic breaking boards?

    I'm a noob at doing MacBook board repairs, it's pretty much a hobby at this point (I buy dead units on eBay and attempt to fix them as practice). I attended Jessa's class and outfitted my bench with tools recommended by Louis and Jessa. This includes a Crest ultrasonic unit. I must be doing...
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