The machine outside NP82 machine increased the remote control system, the motherboard only increased L901 for remote control "standby" state control. So the machine no grating, no sound, in addition to the case analysis on the cause of the problem, remote control system failure also can bow {this failure. U84service manual download site
(1) check C906 boot on both ends of the voltage is 300 v, explain the power rectifier, filter circuit work normally. U84service manual download site
(2) the switch power supply output measurement C909 + B voltage of 0 v, switch transformer without "squeak" sound, switching power supply does not work. U84service manual download site
(3) to measure on the control panel to the mainboard plug 02 voltage is 11 v, that is equal to the work in "standby" state, Q901 conduction the stop of switch power supply. U84service manual download site
(4) check the control panel on the CPU, IC301 voltage of 0 v 1 foot, right. Test the Q3016 collector voltage 12 v, is correct. The suspect Q3017 breakdown. Remove Q3017 resistance measurement. After the replacement 3 cg21b, returned to normal.U84service manual download site