Recent content by Zebulon

So I went and took my A2779 MacBook apart in order to view the area. My logic board is 820-0284-05 and the one I am repairing is 820-02841-A. The area I was questioning you about IS populated with everything I added back, so although I am not sure if the revision makes a difference, it appears...

It's not easy to find 2informaticos. My main MacBook is the exact year, but higher end (larger SSD and more GPU cores). I'm tempted to open it up for look, but it would be nice to find images or info to show me what I need to know so I don't have to do it! lol

Or if anyone at all can help me out please feel free to do so.

Sorry, another question 2informaticos ... or anyone else who might have the answers. I am attaching the image of the resistors and caps directly under UT102. This area is a point of confusion to me as, when I received the MacBook this area was missing several of the resistors or caps, but at...

Would it matter that RT103 pin 2 was corroded away and I got rid of the 0k resistor and ran the trace to connect the circuit to pin 1? Everything that would have gone to pin 2 is now connected to pin 1 after bridging that.

Yes, I'm lost on what more I can do or check. I have looked over this board for many hours and have fixed anything I could find, but still something is not good. I have taken a photo of the section of the board, behind U7700. It might be important as it was the worst looking area from the liquid...

Sorry 2informaticos I lost track of the info you already helped me with. Ok so 1.27v looks close enough. I've gone through all of the similar sensors and the voltages look the same as QD520, but maybe I'm missing something. Other than the schematic is there a list of sensors and voltages...

PBUS_VSENSE (CD520) = 1.27v Should it not be 12v?

Does that look about right now 2informaticos?

QD520 pin 1 = GND pin 2 = 1.8v pin 3 = 12.02v pin 4 = 12.02v pin 5 = 5.98v pin 6 = 0v

Could it still be a resistor around QD520 or something else entirely?

Sadly (Very sadly) that was not the problem. :(

Thanks 2informaticos! I will replace that and I'm feeling good about that being the problem. I guess I'll have to order it, unless I can find it on an old board. I have many old Intel boards all the way up to 2020, but if there's a suitable replacement on those I can't find it using the part...

QD520 pin 1 = GND pin 2 = 1.8v pin 3 = 2.9v pin 4 = 12v pin 5 = 2.9v pin 6 = 0v RD521 pin 1 = 2.9v RD521 pin 2 = 0v RD520 pin 1 = 12v RD520 pin 2 = 2.9v R8320 pin 1 = 1.2v R8320 pin 2 = 0v

Powered up RD522, RD223 and pin 1 of CD520 = 336.4mv No power or battery connected RD522 = 16.8k, but should be 43k RD523 = 5.9k, but should be 5.1k I can't see anything wrong around U8100. Looks very clean. I sure hope it's not U8100 :(