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Yeah only 3v0_g3h fails sometimes, R7020 and F7000 are always correct, as well as 3v3_g3h.
I checked U7800 for ANY trace of ANYTHING and it's completely clean. It's either correct or at .3v, but a steady .3v. I'll try reflow first, then probably track down bad caps if possible.
It stays on as...
Yes. It's dead 90% of the time, but randomly if left on the charger it will turn on. I'm guessing bad cap along 3v0_g3h, but just looking for help. Backing up data right now since it's on before I do anything.
Same thing a few people have had here. No liquid damage, customer says he took it to the beach and it wouldnt power on after a while. Checked inside and all i could find was a bit of dust, literally no signs of liquid damage.
After doing a bit of research I tracked down RTC_RESET_L as...
Got Pro Retina board that boots fine but will not recognize battery.
History: was liquid damaged, completely dead, cleaned by someone, but that only brought it back to power on without charging/running off battery.
ISL current sensing circuits are good: 17/18 are .1ohm/2.3ohm; 27/28 are...
informaticos that was the answer I was looking for, thank you so much! I changed u8900 just to be safe earlier, but that makes a ton of sense. Thank you. We should probably close this and marked solved.
Gotcha, I'm a little worried right now because it black screened during an OS installation, so I'm hoping it's not U8900 that just went bad. After restarting it's installing again, we'll see what happens. I'm going to stress test it to make sure I don't get any graphics issues.
820-3332 board with no liquid damage, no drop history.
Battery would be recognized and would stay at 0% (customer said it wasn't booting). Reflowed U8900 as per Duke's advice in another thread. Battery immediately displayed correct voltage.
PPBUS_G3H on Charger without Battery: 12.59v
Hope all is well. I need some help with a 3330 that's killing me. Has fan twitch and pulsing rails. 3v3_s5 & 5v_s5 are steady. 3v3_s3 & 5v_s3 are pulsing (so is PM_SLP_S4 so I guess that makes sense). 3v3_s0 and 5v_S0 are not pulsing, they're at a steady 0.13v.
The other peculiar...
Sooooo.... turns out that my technicians are idiots. They damaged the new and old trackpad somehow, tested a new one that I overnighted and sure enough it works. Additionally the customer was complaining about GHOSTING, not it not working at all. Replacing U4801 fixed that issue. They previously...
Would there be any voltage on the MISO/MOSI lines? Or are they just data lines? I AM getting 0v on some of the data lines (not the z2 lines) so that may be a clue? I replaced Q4801 thinking that maybe it was shorting and disabling the trackpad. The click function KINDA works, i have to push it...
Hey all, same nightmare issue a lot of people have had. Troubleshooting I've already done:
- Using known good trackpad
- Using known good cable
- Tested continuity from end of Trackpad Cable to U4801
- R4801 reads .01 ohms
- Pin 1 - 3.3v
- Pin 4 - 5v
- Replaced U4801 after all diode readings...
Sorry duke, never got a chance to measure. Finally replaced it with a known good SMC (off a board I was planning on using in the future) and it greenlighted. I guess I just had dead SMC's. Computer needs a new battery, new keyboard, new trackpad, new LCD, and board repair. Customer is going to...
I'm at a loss here, unless I have a bunch of bad SMC's (ive replaced a ton before, never killed them from heat) I have no clue where to look next. SMC_ONOFF_L reads at 3.3v so not sure if that could be an issue... Is U5110 not turning on?