Xiaomi 161201-AA Notebook Won't Turn On repair

Xiaomi 161201-AA Notebook Won’t Turn On repair

Machine model: Xiaomi 161201-AA notebook

Malfunction: Notebook Won’t Turn On

Maintenance process:
Received an Xiaomi 161201-AAnotebook, fault description The notebook won’t turn on.
Dismantle the machine, check that 19V is normal, charging VCC is normal, 5V VCC is normal, all peripheral devices are disconnected for testing, and there is no response after starting the machine, which basically eliminates some problems of power interface TYPE-C and VCC conversion.
After checking, there is an indicator light on the plug-in charger, but there is no startup response when the power-on button is pressed, but the indicator light will go out instantly when the button is pressed, so it is judged that the machine has startup action, and it may be partially Short circuit switch Current protection.

Xiaomi 161201-AA Notebook Won’t Turn On repair Figure 1.
multimeter on/off gear is used to measure each VCC Capacitor. After inspection, it is found that Capacitor in the red circle below is in Short circuit state, and the quantity is a little too large, and it is up to Capacitor Dafa.

Xiaomi 161201-AA Notebook Won’t Turn On repair Figure 2.

Xiaomi 161201-AA Notebook Won’t Turn On Maintenance Figure 2
Find the DC-DC power supply of Short circuit, set DC power supply to 1V, turn on Current heating test, and find that Capacitor high temperature next to the sound card is serious.
After dismantling Short circuit Capacitor, test other Capacitor no longer Short circuit, power on the test machine, and 3.3V will return to normal.