故障表现为:不定时跳菜单 分析与检修:上机架测试,不定时出现菜单,测量排插P004的2脚电压为2.7V,正常为3.3V,说明按键供电不正常,将C5去掉故障依旧,测量U001供电,74脚电压为2.38V偏低,正常为3.3V,测74脚至STB3.3V间阻值为九百多欧姆,应为过孔不良,飞线STB3.3V至U001的74脚,电压恢复正常,故障机修到这里,终于修好值得探讨。。 |
|Archiver|手机版|家电维修论坛
( 蜀ICP备19011473号-4 川公网安备51102502000164号 )
GMT+8, 2025-7-18 09:48 , Processed in 0.123511 second(s), 17 queries .
Powered by Discuz! X3.5
© 2001-2025 Discuz! Team.