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Conventionally, this " failure " do not seem to repair , according to the power switch directly open, shut down the line. Taking into account the functional integrity of the aircraft , as well as respect for the user's operating habits, we still pick repair. From the failure phenomenon , the problem lies in the standby circuits or microprocessor circuit . Due to the remote shutdown when not everything is normal , but you can watch in normal remote shutdown , you can remote boot, standby circuit fault can basically rule out the possibility , therefore determine fault in the microprocessor (CPU) circuit .cznservice manual download site
The machine CPU uses MNl5142TEAI, its power control terminal ¢Þ feet , in the boot and normal viewing state of the pin are high voltage 4.3V, the standby state is 0V. Through the power switch by measuring CPU ¢Þ pin voltage is 4.3V, in working condition ; shutdown using the remote control power switch off , press the power switch again to boot , then matt silent , standby indicator light, measuring CPU ¢Þ pin voltage is OV , confirmed that the CPU is in standby mode and can not lead to the first boot failure. ? So, what causes the CPU is in standby mode it analyzes think there are two possibilities: First, CPU failure, the second is when the remote shutdown caused a CPU internal logic disorder. From television to work properly , the possibility of the former is unlikely, therefore focus on examination of the latter. In theory , the impact on the CPU power is nothing more than the remote shutdown switch on the CPU , of course, including the impact on reset circuit . But supply -side CPU 39 feet measured in the normal state and the watch has a normal standby supply voltage , carefully check the reset circuit ICll06 (MNl280-P), Cll03 other components are no exception , try replacing +5 V power supply filter capacitor C1134 invalid. CPU seems to be a problem , causing disturbances on the logic appears after remote shutdown. No special plug- coupled machine memory , but integrated in the CPU inside , confirm the fault lies more in the CPU, but the fault persists after replacing MNl5142TEAl .
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