Search results

Customer just said it started turning off one day. Hasn’t had liquid damage, can’t see any sign of it. Will check those in a moment.

I have an 820-01521 here that gets hot and then turns off. I have linked a video below from the thermal camera to show what is getting hot. The cpu is getting red hot, the first IC that appears to be hot is U7210 and also L7210 is getting red hot. I'm not sure if u7210 is bad, or if the cpu is...

Dfu restore on a Mac ? , I thought that was for iPads , phones

If I hold D and go into diagnostics it stays on, if I boot into option R recovery it goes off after a few seconds once booted. If booted normally it goes off after 1-2 mins.

They said “Hi I have a macbook air which keeps shutting down unexpectedly. This can be only after a couple of minutes and when doing low intensive work like writing an email. “ Iv taken the board out and inspected it under the microscope on both sides and don’t see any water damage at all or...

It’s a 820-01521-a

Have a MacBook Air a1932 in that boots ok, stays on for 1-2 mins, the screen goes black, then a few seconds later the macbook turns off. In diagnostic mode no faults are found, it will happily stay turned on in this mode. if I put it in system restore internet recovery it boots into the UI and...

Ignore that I had it in resistance mode, tests fine in diode mode. Have ordered a bios programmer to see if re flashing it helps,

In diode mode it shows 0.440 on that test point

I have just noticed this next to the bios chip, I’m not sure if it is relevant as it doesn’t actually connect to any surface traces. The line is SPI_MOSI and shows OL at that test point.

Reballed SMC, will has the same problem

No sign of corrosion under the SMC, just pulled it and looks fine. Is it possible U7501 is damaged ?, as R7523 was damaged. Not sure if the voltages it produces are there?.

Thanks, is the CPU not underfilled on these, or is that just phones and ipads ?. Ill give the SMC a reball. What temp is safe for the CPU ?.

Ok I took them out of circuit and they test fine, so all three of those are good.

R7523 was the one I replaced as water damaged, it’s within spec. R7520 has a very weird reading, so going to change it. R7521 also a bit off so will change that.

PCH VCCSDIO BYPASS / PP3V3_S0 / C1208 - 3.2v pulse detected PCH VCCSUSHDA BYPASS / PP1V5_S0SW_AUDIO_HDA / C1210 - 1.4v pulse detected (PCH 3.3V GPIO/LPC PWR) / PP3V3_S0 / C1212 - 3.2v pulse detected (PCH 3.3V THERMAL PWR) / P3V3_S0 / C1214 - 3.2v pulse detected (PCH 1.05V ME CORE PWR) /...

PP3V3_S5 - 3.3v P3V3_SUS - 3.3v PP3V3_SUS - 3.3v PCH VCCSDIO BYPASS / PP3V3_S0 / C1208 - 0.101v PCH VCCSUSHDA BYPASS / PP1V5_S0SW_AUDIO_HDA / C1210 - 0v (PCH 3.3V GPIO/LPC PWR) / PP3V3_S0 / C1212 - 0.100v (PCH 3.3V THERMAL PWR) / P3V3_S0 / C1214 - 0.100v (PCH 1.05V ME CORE PWR) / PP1V05_S0 /...

Ok I have tested all resistors and traces and all testing good. this is a video of what is happening with the board. https://youtube.com/shorts/11JFKIq36qA?feature=share

Ignore that Iv found the page on the schematic

Iv had a look and j6100 is clean and has no corrosion at all. Iv had a look on the schemetic and see lots of references to spi, but not sure what you mean by the SPI Bus Series Termination resistors ?.