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Prior to putting in DFU this board had liquid damage to LCD backlight area. That was solved and I could see cycling of power rails. I could see .8V on CPU rails cycling power briefly. So I thought maybe T2 issue. Was able to get it in DFU mode and have tried restoring the T2. It gets to 4th step...

Going to be a no fix. All I can guess is maybe T2 issue. Connectivity on U3701 seemed pretty good and couldn't find any issues with the caps or resistors around it. Inspected the board again and just not seeing anything out of place.

From what I can tell, it is solved from just clean ME. I have tried roughly dozen times and it is no longer hanging up and waking as it should. Thanks!

No bluetooth or Wifi hardware detected in system info. It shows software versions only for wifi. So, I had tried pulling U3701, U3710, U3750 from another 01598 board and I believe it went pretty well as far as reballing the donor U3701 and placing. I thought that would've resolved any issues or...

No history on this. Board was clean. A2159 820-01598 that has no wifi for no known/visible reasons. 1.8V and 3v3 are present so I believed it was the wifi chip itself. I tried reballing it but no change. I tried pulling same part number wifi chip from other board with associated ROM chips and no...

No luck. Issue persists.

This Mac operates normal except for when it is sleep for while it won't wake up with key press or power button press: the backlight comes on with no image. It will wake up if I close the lid and wait a bit and reopen. I did PRAM resets and update. I tried messing with some settings via terminal...

I tried at least 3 new batteries and a used original but then realized SMC_ON_OFF was being pulled down. However, I just realized that something I changed of the previous fixed the SMC_ON_OFF issue and in addition a new battery has now solved it from rebooting.

I went back through everything in the CD3215 area and discovered R3108 was open. Replaced it and board came back to life. Everything worked 100%

This was working fine. Then shut down and wouldn't stay on. i realized it will only stay on with trackpad unplugged. I tried replacing Trackpad and the TP cable. Replaced U4850. Then noticed something pulling down SMC ON_OFF when trackpad plugged in. Removed C4810. Checked R4810 and R5170...

No luck. T2 probably no good?

One of the CD3215 was damaged (u3100) with liquid and not taking 5V. Replaced and now all ports go to 5.1V .2A w/ PPBUS_G3H at 12.3V but not boosting to 20V. no shorts on major coils that I can detect. SSD voltages are not present but SSD_PMU_RESET_L is present. Does this mean U9000 is likely...

Very much appreciate that tip. I wouldn't have guessed it would boot without U2800 considering how Apple is tying everything together before booting. Yes it does in fact boot without the U2800. SO hopefully replacing it will get me back in business. Thanks again!

PM_BATLOW was stuck low. Checked and near 0 in diode mode red to ground. When I pulled off shield on U2800 a bunch of caps and diodes moved near DCIN ports. I put everything back pulling parts from different board and thought everything was good. Plugged in and board started to try to start and...

Yes. PM_PWRBTN drops from 3.3V to .3V when triggering SMC_ONFF_L

Was in the title: PPBUS_G3H is 13.1V without battery. I’ll report on the others tomorrow. Thanks!

No signs of liquid. Machine died for no known reason according to customer. PP5v_S5 and PP3v3_s5 are present. Checked diode on all big coils and checked with IR for any heat on board. Tested on bench with only power cord plugged in. Doesn't start in SMC bypass. PM_EN_5vS4 is not present. S5...

Thanks for your help. I DID figure this out. I pulled Q7180 again and under the scope when touching up those pads on the board again there was a little thin layer of pink plastic ribbon on one of the pads. I looked at the bottom of Q7180 and there is a thin layer of pink plastic that was...

R7180/1/5/6 all measure correctly and I have checked for continuity from all points of Q7180 to the according traced points on the board.

1- 0 2- 16V 3- 4V 9 - 0V 12 - 3.4V 13 - 3.2V 14 - 3.2V 15 - 0 17 - 1.2V 19 - 5.5V 20 - 5.5V 27 - 1.2V I've changed Q7180 and U7100 multiple times and same results. I've tested traces from Q7180 also