Blue sky motherboard gaijixian maintenance

Blue sky motherboard gaijixian maintenance

Motherboard model: NH50DPMB-0D

Motherboard failure: the graphics card PEXVDD power supply burned, and the core was taken away.

Main board maintenanceProcess: The burnt area is too large, and it can’t be repaired by itself. Communicate with customers and agree to change the set display. Then dig and dig on the small motherboard, and dig to the public point without short circuit.

(PS: Be sure to dig up the burnt black substance completely. )

After digging clean, find the power supply control chip of the graphics card and pull the 12 feet to the ground.

In this way, the power supply of the independent display part will not work, and the power-on test will turn on the machine perfectly. Of course, if there is no independent display in the blue sky, the fan will turn off for about three minutes, so it is necessary to make some changes to the circuit, find the independent temperature control SM bus, and remove Q14.

Find a temperature detection chip at random, reset the clock of SM bus, and fly the four wires of power supply and grounding, leaving the other pins hanging.

After the flight, it was fixed, installed and tested, and the power was not cut off, which was a perfect call.

Maintenance result: The mainboard was installed, the startup test was successfully lit, the recording, camera, sound and WiFi were all normal, and the stress test of the baking machine was normal for half an hour, so the maintenance was over.