201212301102454.jpg (28.72 KB, 下載次數(shù): 2)
下載附件
保存到相冊
2015-7-24 16:26 上傳
故障現(xiàn)象: 三無(燈亮)
機(jī)芯: UL21飛利浦單片
機(jī)型: 2513UI,AT25135,AT25215Z,AT2516G,AT2516UG,AT25286,
AT2527,AT25181,AT25166(I),AT2565,AT2565A,AT2565(F),
AT2570UB(I),AT25189B,AT25276,AT25166,AT25206,
AT25276G,AT2565(I),AT25286(F),AT25166G,AT2560B,
AT2590B,AT2590UB,AT25166U,AT25106B,AT25215ZU,AT2575B,
AT2570UB,AT25211A,AT25166I,NT25A11,NT25A21,NT25A51,
AT29189B,AT29106B,AT25289B,AT34189B,AT34281,AT34187,
AT34276,AT34276(F),AT34286,AT34286(I),NT34181B,
AT34U186,2926UI,AT29266,2927U,2927U(I),AT2975,AT29166,
AT29128,AT29286,AT29187,AT29166UG,AT2916UG(F),
AT29166(I),AT29286(I),AT29166G(F),AT29286(F),
AT2960B,AT2916UG,AT25266,AT29215Z,AT29229,AT29329,
AT29386,2526UI,AT29211A,AT2988U,AT2990U
檢修過程: 19 "機(jī) 型:HD29A41A 故障現(xiàn)象:不開機(jī) 維修過程:開機(jī)B+在40V左右波動,測電源厚膜塊5Q1265的3腳在11V-13V間波動,并且開關(guān)變壓器發(fā)出吱吱有節(jié)奏的響聲,測負(fù)載未見有短路的 地方,將光偶取下,在3、4腳間接一10K電阻,故障依舊,說明故障點(diǎn)在初級,測5Q1265的5腳(同步控制)的外接電阻R805(470Ω)阻值為 17K,更換后,通電試機(jī),仍不開機(jī)。斷開電源部分的負(fù)載,強(qiáng)制開機(jī),B+正常,說明電源無故障,測數(shù)字板ST-5V供電為3V,明顯偏低,且R847發(fā) 燙,分析為5V負(fù)載有過流情況,更換數(shù)字板上的TDA12063后,開機(jī)正常。 "
故障板名稱: 主板
故障元件位號: DA12063
處理措施: 更換
圖片: 無
|