This machine boot display state, a PC can't switch to the "INPUT1" state, also don't show "INPUT1" characters on the screen. Press the switch key always show PC status. Video input signals. UxMservice manual download site
 UxMservice manual download site
Enter the self-checking, IC3003, IC3004, IC3005 have shown "NG", judge fault in J board, the computer also no signal, further confirm the fault in J board. UxMservice manual download site
 UxMservice manual download site
First several measurement shows that the "NG" IC power supply, IC3003 and IC3004 power supply is standby 5 v, the power supply is P5V IC3005, limited by the installation structure, several is not easy to directly. Had to first measure the voltage on the J3 and found that J3 1 foot without standby 5 v. And measuring the D3 1 foot has a 5 v carefully observed D3 on the plug end of the pry up slightly. To insert the plug, troubleshooting.UxMservice manual download site