1. DrunkenMonk

    OP DrunkenMonk GBAtemp Fan
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    Had this switch come in, replaced the USB port and found it still wasn't working, all values seem okay on m92 test points, battery charges fine - but the system won't display anything, just the backlight turns on when injecting a payload from the system hitting auto recovery mode.

    So first image here, the cap marked with a red box is shorted out, subsequently the resistor is shorted on the side marked with the yellow box. However upon checking that resistor it measures completely different to a different switch (we're talking a huge difference from one reading 35k and the other reading 80k)

    v

    IMG_20191211_210523.jpg

    Second image here, originally these two were bridged on the north-facing side, which I'm guessing the person who attempted the repair before me somehow managed to do? and possibly killed that tiny IC below? But I just don't know enough about how the image is driven or if it entering auto RCM without ever being modified is caused by something else (though this seems like it would be a good reason to)

    Untitled.png

    Anybody have any thoughts or experienced something similar?

    I've looked at the markings on the top of that IC and it looks like:
    Untitled2.png
    8316
    7J14

    Though I can't find a reference to what it is or anything of the sort
     
  2. Pintglass

    Pintglass GBAtemp Regular
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  3. DrunkenMonk

    OP DrunkenMonk GBAtemp Fan
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    Great, thanks - so now I know VREF is definitely shorted, subsequently shorting NON1 too(or maybe it's actually NON1 that's shorted?), and I can't seem to be able to find the short originating from anywhere else, so I guess the only course of action seems to be to replace this chip? Though, sourcing just one for a reasonable price appears to be difficult.
    Would you happen to know of any UK suppliers? Or even Chinese suppliers that'd ship quantities of 1-5 for reasonable prices aha
     
  4. Pintglass

    Pintglass GBAtemp Regular
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    Farnell have them.
     
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