HP TPN-C125, shut down automatically from time to time for maintenance!

HP TPN-C125, shut down automatically from time to time for maintenance!

I received a HP computer from my colleague, saying that it always shuts down automatically. He took it apart, cleaned the dust and replaced the silicone grease, but it still failed. The baking machine tested that the CPU and graphics card were normal and would not shut down automatically, but it turned off itself after working normally or standing there for a while.

Get the machine and bake it for a few hours. Test that everything is normal and it will not automatically cut off power. First of all, I wonder if it has something to do with sleep. If I turn off the sleep standby test, it will still automatically cut off the power. I wonder if the memory is unstable, then open the memory test tool and test it is normal; Because there is data on the hard disk, I am afraid to break the system, and I am going to test it in WIN10 PE. I just entered PE for less than 30 seconds, and the power was cut off. I tried it several times and it was the same. I wonder if the BIOS version is too old. I went to official website to download the latest online BIOS update. After the update, PE directly reported the error BIOS_ACPI_ERROR in blue screen, but the problem of power failure was still unsolved!

It seems that there is something wrong with the motherboard itself. Take a look at it!

Machine appearance drawing

惠普TPN-C125不定时自动关机维修

Fuselage model: TPN-C125

惠普TPN-C125不定时自动关机维修

Main board version number: A-C701P REV:1.0

惠普TPN-C125不定时自动关机维修

After electrifying, the major power supplies were measured, and there was no abnormality. Then, touch with your hand to see where there was any temperature abnormality, and it was found that the temperature of PL14 inductor was particularly hot, which was the CPU power supply inductor. Because the baking machine takes too long, I’m not sure whether the CPU temperature is too high. After cooling the machine, I feel the temperature change of PL14 with my hands while turning it on, which is really a very fast temperature rise.

惠普TPN-C125不定时自动关机维修

Replace all the upper and lower tubes, filter capacitors and inductors of this power supply.

惠普TPN-C125不定时自动关机维修

Start the test again, the temperature of PL14 is normal, stand by for several hours, and there is no automatic power failure, so the maintenance is over!