Observe disconnect + 210, + 79.5 B B voltage of load, on the R893 and a 40 w bulb, after switch on the light bulb not bright, bulb on both ends of the voltage measurement for only a few volts. dMxservice manual download site
 dMxservice manual download site
Measuring microprocessors IC901 28 feet (TVSA0185) voltage of + 5 v, normal. Panel on orange leds light up, vice power and microprocessor basic work properly. Have "squeak" sound, switch power supply has been up, but because of the load or voltage feedback circuit in fault and the abnormal output of switch power supply. dMxservice manual download site
 dMxservice manual download site
Detection + 22 b, plus or minus 12 b voltage circuit load resistance, no exception. As shown, use oscilloscope to detect IC821 (M62281FP) (1), (5) feet of waveform and voltage, all normal. With alcohol cotton PC821 daub and three-terminal voltage regulator IC852 (TL431A), fault is still. The last try to replace (TL431A), troubleshooting.dMxservice manual download site