For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
Ah, ok that's some good info to have. That measurement has had me scratching my head for a bit. I'm just getting started out, so I thought anything that didn't read 0L was passing current to ground. When is it considered a short, then? Does that just come with more experience with certain...
I just left the board unplugged overnight, and I'm still measuring a 55Ohm short to ground on P3V3_S5. With resistance that low, shouldn't the rail be a fraction of what it should be?
Good guess! If their cleaners weren't so favorably reviewed, I probably would have tried to get something...
I know -- it's super weird, but I never do short or resistance measurements with power applied. I actually went through every single connection on the P3V3_S5 line, which was over 50 measurements on both sides of the board -- no power attached -- and the drop to ground was steady on every...
Hoping I finally get my Crest this week -- derps sent me a basket, but no cleaner :D . I'll run it through that, and see what it does. After that I might take the SMC off and see what's going on underneath -- hopefully the pads are still there.
That said, shouldn't SMC_CLK32K be showing the...
L7560 = 3.345V
PPBUS_G3H = 8.62V on both sides of the board.
I did reflow the SMC, but that doesn't rule out a bad pad or bad SMC -- which would be unfortunate. There was corrosion around some SMC components and on that side of the board, though. Been waiting on my Crest for quite a while...
Ok, I just measured SMC_ADAPTER_EN again and now it's reading 3.39V -- not sure what happened there. I doubled checked the resistor, and it's showing about 10k and there's no short there.
Pin 12 on U1900 = .426V
Pin 2 on R5112 (for SMC_CLK32K) = .395V -- so I'm guessing CPU isn't generating it...
Gotcha, thanks for that!
SMC_ADAPTER_EN is reading 1.042V.
PCH_DSWVRMEN = 3.248V
PM_DSW_PWRGD = 3.418V
I don't currently have an oscilloscope, so I can't check the frequency. :(
Ya, I just figured since the line is called P3V3, it should be ~3.3V -- so 2.005 is correct?
Unless I'm derping out, I always unplug when I measure resistances/shorts. I won't say I wait 20s, but I do wait, and yes the short is present without power.
I am using an original 14.85V charger...
Hey guys, I have this rabbit hole of a liquid damaged 820-3435-B board I'm working on. Initially, I started out replacing R5100 -- it was so burnt, it basically fell off the board. Also, the board had a couple broken paths by traces I was able to repair easily by C5001/L5001...