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This lesson talks about the analysis when the reset signal is short-circuited

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Open the schematic diagram of Xixomi 11

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This is the reset signal, it goes to the pin 45 of the connector J6503

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Switch to bitmap

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This is the pin 45 of the touch connector, the reset signal

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Click on it and you can see that it leads to a capacitor that has ground pin

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It also leads to a resistor with no ground pin on either end

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At the same time, it leads to the pin C28 of the chip U3100

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When there is a short circuit in this line, how to analyze it

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First remove the components that are grounded at one end

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Components that are grounded at one end have a capacitor, a CPU,

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and they both have a ground pin

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Specific maintenance steps

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First remove the capacitor and measure pin 45

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If there is no longer a short circuit, it means that the capacitor is damaged,

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and the fault is repaired

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In another case, when the capacitor is removed for measurement, it is still short-circuited

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At this time, it is necessary to remove the CPU, re-solder it,

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and measure whether there is still a short circuit

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If there is no short circuit, the fault is repaired

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In another case, after re-soldering the CPU, there is still a short circuit,

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which is basically irreparable

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Either there is a problem with the board layer, or the CPU itself is damaged

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That's all for this lesson