1. note9

    OP note9 Member
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    Hello, I have an unpatched switch that's not recognised by PC so i cant send a payload. It can charge fine. measured the usb pins and on the A7 D- pin i get OL, A6 D+ i get 0.781 using diode mode.
    anyone have a solution?

    thanks
     

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  2. FXDX

    FXDX GBAtemp Regular
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    If the USB port is OK, then you need to turn your attention to the MAX77621, MAX77620 chipsets and nearby capacitors. If everything is ok there, it is possible that the problem is from Tegra SoC, where you can try a reball.

    Charging_Port_Edited_2.jpg
     
  3. thesjaakspoiler

    thesjaakspoiler GBAtemp Fan
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  4. note9

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    @FXDX, are the USB data lines connected to those MAX chipsets?


    @thesjaakspoiler, I took it out, it was shorted. Some boards don't have it.
     
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  5. note9

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    took out the usb-c port and now that line is showing as shorted to ground.
     
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  6. FXDX

    FXDX GBAtemp Regular
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    Reball or reflow Tegra SoC.
     
  7. Ttm3

    Ttm3 GBAtemp Regular
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    I've had several of these where the pins in the charge port get bent. This can short the chip in the data lines just above the charger or open the filter just above that resulting in no access to RCM. I've also had it damage the tegra. System still works as normal but the data lines won't communicate with tegra resulting in no access to RCM
     
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  8. note9

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    i'll try reflowing as i only have a hot air station at the moment.


    is there a photo showing where those pins go on the SoC?
     
  9. Ttm3

    Ttm3 GBAtemp Regular
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    I don't have one. I always assumed it damaged that circuit going through the processor & was not a reflow candidate.
     
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