Hi all., I am working on a MacBook 12" Retina Logic Board # 820-00045-A. It does not turn on. The Amp meter show 20v & the amps are around 0.01 ~ 0.05V . Upon checking all the power rails, till PP5V_S4 all is fine, getting full stable 5V on this rail but when I check PP5V_S0, it is fluctuating 5V , after a sec it goes to 0V & comes back again to 5v. This is happening continously. I checked for any short to GRD in diode mode but none. For where is this PP5V_S0 generated?? No liquid spill, logic board is very clean. Any help or tips will be great appreciated. Thanks
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Last edited by mferna14; 11-10-2022, 04:34 PM. -
Re: MacBook 12" Retina 820-00045-A PP5V_S0 fluctuating
https://www.youtube.com/watch?v=F-sTAO9BEqE
https://boards.rossmanngroup.com/thr...o-power.44744/
What is the voltage of PPBUS_G3H ? -
Re: MacBook 12" Retina 820-00045-A PP5V_S0 fluctuating
Thank you so very much mon2 for all rescue of mine & infact ours.... Anyway all done, had to re-flow the U7600 (U7600 SN650801 Power management IC) & all worked. Signal is generated from this chip P5VS0_PHASE... Since the balls under the chip had loose connection this is why PP5V_S0 was coming & going away contin'. After a good re-flow all worked fine. Thanks for the help.Last edited by mferna14; 11-10-2022, 07:14 PM.Comment
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Hello everyone,
I'm currently diagnosing a MacBook Pro A1707 motherboard that does not power on. I've gathered some data but am stuck and need expert advice.
Note that i'm a beginner in electronics and i'm trying to learn while trying to repair this macbook that my work gave me. I'm really curious and love understanding how thing works and i already learned so much.
Only one usb c port is taking 20v and have 12.5v on PPBUS_G3H. when trying other ports, 2 are not going to 20v and one is going to 20v but the CD3215 is getting really hot.
Observations... -
Hi everyone!
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