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In this class, we will talk about how to repair the trigger protection

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caused by the short circuit of the CPU and the temporary storage power supply

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As we mentioned earlier,

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short circuits in the power supply of CPU, temporary storage,

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and hard disk are the most common

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Let's take a look, how do we repair it when this happens?

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As mentioned earlier,

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how to find its power supply and where to measure the power supply

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Today we talk about how to repair

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First observe the capacitors and chips on this line,

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whether there is water corrosion around them

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This is number 1

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We first observe the capacitor on this line,

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the chip connected to this line,

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and whether there is water corrosion around the capacitor and the surface

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If we see that there is a capacitor corroded by water on this line,

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we remove it first,

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and then we measure the ground value of this line to see if it is still short-circuited

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Then there are two cases

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In the first case, after we remove the capacitor,

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there is no longer a short circuit,

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indicating that the damage to the capacitor caused the short circuit

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If we just removed 1 or 2 capacitors, we don't have to replace them

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If it is still a short circuit,

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we have to continue to find the capacitor with water corrosion until it is no longer short circuited

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Okay, this is how to repair the capacitor with water corrosion on this line

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If the capacitor is not corroded by water,

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there are traces of corrosion around the chip on this line,

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and this chip is not sealed with black glue,

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how do we fix it?

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We take off the chip and measure this line to see if it is a short circuit

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We will encounter two situations

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First, after we remove the chip, it is no longer short-circuited

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We need to remove the tin residue on the surface of the chip,

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reball it, and then re-solder it and measure again

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If there is no short circuit, the fault has been repaired

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What is the cause of the short circuit?

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In fact, the impurities after corrosion caused the short circuit,

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and the chip was not damaged

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In the second case, after re-soldering and measuring again,

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the line is still short-circuited,

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indicating that the chip is damaged and the short-circuit is caused,

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and we can repair it by replacing the chip

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If the circuit is still short-circuited after removing the chip and measuring again,

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we will use the burn-in method to be discussed in the next lesson to repair it

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Ok, this is how to repair the short circuit caused by water corrosion

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That's all for this lesson