Received peer fixing G450 lenovo notebook, press the power button, indicator lights, boot the machine no display, remove the battery, connected to the adjustable power supply test, instantaneous current is 0.56 A, is obviously not normal, press the boot key, current pulse to 0.58 A, this machine has A disease, generally does not display the boot is on the right side of the USB interface damage caused, so check the interface does damage, but there is A problem in the standby current is 0.56 A absolute, then teardown detection, out of the bare plate test, found on the occurrence of the burned directly out of the hole hole

Obviously, occurrence of burn, and replace the occurrence of the chip

Make value after dismantling the occurrence of the USB interface resistance infinity, all is OK, then replace the occurrence of the new chip, completed all worth around 520 ohms, light machine electricity test machine, test perfectly using USB interface, the machine has been fixed