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Is this correct? PP3V3_SUS is created by U8020. U8020 will only create it if: PP3V3_S5 is present AND if P3V3SUS_EN is present. However, P3V3SUS_EN is 0 Volts. P3V3SUS_EN requires PM_SLP_SUS_L, via R8190. R8190 measures 98ohms, so is OK. PM_SLP_SUS_L comes from the CPU U0500... and as there...

Hi again 2informaticos. I removed LIO flex. No PP3V3_SUS. :( I checked P3V3SUS_EN = 0v PM_SLP_SUS_L = 0v In regards to checking the 4 PCH's RTC signals... what pins should I be reading with an oscilloscope? I can only see PCH_CLK32K_RTCX1 in the board view...which I should be able to get a...

Hi again. I have a 820-00165 that came in with a very small amount of water damage, but very little sign of corrosion. Originally completely dead, but I found a tiny amount of corrosion on J9500, specifically around pin 19 SYS_ONEWIRE. I cleaned and reflowed, then added some enamel wire and...

Hi piernov and 2informaticos. Sorry for the delay. I did try it with two brand new aftermarket screens, however both were from the same supplier. We buy quite a lot different mac screens from that supplier, and rarely have issues, but I think this is the first time we've bought that particular...

AH, OK, Thanks for that. I'm not very familiar with this model I disconnected the webcam side of things... but still no change unfortunately. The screen looks perfect with Apple logo, and at the login screen, until I input the password, then it goes very dim. However, a correction - the...

Hi again 2informaticos. Thanks for your help, once again. The webcam data lines seem to be integrated into the EDP cable that connects to J8500. I don't think there's a way to disconnect the webcam...short of opening the panel, is there?

Hi. I replaced a cracked display assembly in a customers Macbook Pro A2159 (13", 2019). On starting, the Apple logo, and the login screen, appears fine, however, once you input the password and actually login, the screen dims. The brightness control slider on the keyboard is responsive, but it...

Ah. OK. I think thats probably the most likely. I'll move on. Thanks for your help and advice, 2informaticos, I do appreciate it.

Any suggestions?

Sorry for the delay. I had to put this on the backburner for a bit. OK, I replaced the BIOS chip from another 820-3437-B, and no change. :( I did notice the CPU is getting very hot. Still no display internal or external. SMC reset cycles Magsafe light, power button starts and stops system....

Hi again 2informaticos. Thanks for your suggestions... I'm still learning, as you can probably tell. :) All good points you make. I posted all those different voltages in case you wanted them, to save time... but yes... that was a waste of time, lol. I'll find another C5002 equivalent from a...

Tried with an external SSD adapter, that flashes when plugged in. The light comes on for a second, then turns off and stays off. Rechecked 3V3/5V_S0SW_LCD - both zero volts.

Hi again. That doesn't sound great. :( I plugged in a USB mouse, via a cheap Keweisi branded USB volt/amp meter, and I get a light on the mouse. The voltage is 5.10, The amp draw is 0.29A. The external screen, connected to either usb port, does light up the white LED to indicate it detects a...

Hi all. Macbook Air A1466 with a 820-3437-B Logic board. Bought in as not powering on, no lights, display, chimes or fans. No evidence of liquid ingress - very dusty though. Found shorted C5002 on PP3V42_G3H rail. Removed and that restored Magsafe light and fan- still no chime and no display...

Hi again 2informaticos. Did you try known good USB-C hub? No... but I shouldn't need one, should I? I'm going directly from USB-C, to the USB-C on a Asus USB-C panel. I've tested it from both USB-C ports, and it has the same symptoms... light on monitor changes from orange to white when I turn...

Ah, OK, that makes sense. I resoldered the 3x coils and F7000, checked in diode mode - approx 0.400. So fingers crossed, I applied power. I now get the CPU getting hot, and the fan coming on, but no display. The system appears on, as the touchpad clicks until I hold the power button, and then...

Thanks 2informaticos. I changed U7420, and the short from PPBUS_G3H to GTVR_SW2 is gone! However, should Pad2 on L7420, L7410 and L7430 still be 1.6 Ω to ground? Its PPVCCGT_S0G_PH3. Is it normal for it to show such a low resistance to ground? Just thought I'd check before proceeding further...

Hi again. OK. So, I removed them one by one, and of course it was the last one where the short disappeared. So, checking resistance to ground on Pin 2 of F7000 With L7430 removed, resistance dropped to 1.7 Ω. With L7410 removed, as well, resistance dropped to 0.8 Ω With L7420 removed, as well...

Hi, again, 2informaticos, and thanks for your help. With the multimeter on the ohm scale, ground to pin 2 on F7000 is 2.1 Ω Testing all the coils near the CPU, 3 show the same value. These are L7410, L7420 and L7430 all show 2.1 Ω No worries re not injecting voltage on PPBUS_G3H. I don't want...

Hi all. I've got a dead 820-00840, won't power on, no fan. The board has no signs of liquid ingress or other damage. PPDCIN_G3H has 20.1v, tested with two different chargers. PPDCIN_G3H_CHGR also measures 20.1v However, there appears to be a short on PPBUS_G3H, as diode mode reads, with red on...