[post][font=楷体_GB2312][size=3][backcolor=#ffffff][color=#444444]用户反映不通电。打开机顶盒,按下电源开关,面板无显示。测量三组电压,2.85v,15v,0V,正常电压应该是[/color][/backcolor][/size][size=3][backcolor=#ffffff][color=#444444]5v,16v,21V,[/color][/backcolor][/size][size=3][backcolor=#ffffff][color=#444444]怀疑电源板损坏。更换新电源板故障依旧,说明原配电源板没有损坏,问题出在主板。[/color][/backcolor][/size][/font][size=3][font=楷体_GB2312][backcolor=#ffffff][color=#444444]断开与主板相连的电源插线,[/color][/backcolor][/font][/size][size=3][font=楷体_GB2312][backcolor=#ffffff][color=#444444]沿着主板21[/color][/backcolor][/font][/size][size=3][font=楷体_GB2312][backcolor=#ffffff][color=#444444]V[/color][/backcolor][/font][/size][size=3][font=楷体_GB2312][backcolor=#ffffff][color=#444444]供电线路逐一排查,发现C85贴片电容短路(在8550三极管正下方)。去掉电容后,故障排除。[/color][/backcolor][/font][/size]
[size=3][font=楷体_GB2312][backcolor=#ffffff][color=#444444]主板版号:KLF-CXHHT-MB-02 A5,日期2016.10.08 [/color][/backcolor][/font][/size][size=3][font=楷体_GB2312]C85电容击穿是此批次机顶盒的通病。[/font][/size]
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