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Liquid damaged A2141 820-01700 Only powers on with Battery
- Thread starter EsteTron
- Start date
It looks like being used by thunderbolt functions, not for normal USB.
There sholud be something more affected by liquid on the part of pure USB management.
There sholud be something more affected by liquid on the part of pure USB management.
EsteTron
Member
Sorry for taking so long to get back to this one. I was able to determine that when a USB pendrive is connected, the corresponding USB port and CD3217 it is connected to will generate 5v. However, macOS will report an error saying that USB needs power in order to work. I
So the USB ports are attempting to turn on but there appears to be a communication issue somewhere on the logic baord.
Looking back at earlier pictures of the board I took before replacing the corroded U3100 and U3200, I noticed that the Resistors R3100 and R3101 are connected to USB_UPC_PCH_XA were significantly corroded. Both resistors were measuring proper resistance of 0 ohms. However, I think this is where my issue maybe.
I am under the suspicion that when liquid killed U3100, the line USB_UPC_PCH_XA may have been over volted and killed part of the PCH.
Since I have been working off an on with this one for a few months and potentially having a PCH issue, I am deeming it irreparable here. I hope this logic makes sense.
So the USB ports are attempting to turn on but there appears to be a communication issue somewhere on the logic baord.
Looking back at earlier pictures of the board I took before replacing the corroded U3100 and U3200, I noticed that the Resistors R3100 and R3101 are connected to USB_UPC_PCH_XA were significantly corroded. Both resistors were measuring proper resistance of 0 ohms. However, I think this is where my issue maybe.
I am under the suspicion that when liquid killed U3100, the line USB_UPC_PCH_XA may have been over volted and killed part of the PCH.
Since I have been working off an on with this one for a few months and potentially having a PCH issue, I am deeming it irreparable here. I hope this logic makes sense.
CD3217 must send out 5V to VBUS, when USB device is detected on its port.