冠捷系列机器维修案例

1、广州分公司向易泽广州分公司向易泽2007-08 机型：LCD37K72 故障现象：无声音 检修过程：通电开机发现有图像无声音，首先检查伴音制式无误后，测功放供电为18V正常。用示波器测U503（MAX9704）功放输入波形（10、16脚）正常，检查功放静音控制脚为低电压，说明静音起控，查Q502时C、E脚已短路。更换零件后故障排除。 维修总结：此机型极易出现无声故障，多数为功放供电开关管Q701（AO4403)不良,Q701为场效应管,主要控制18V向MAX9704供电,常见故障是源极与栅极击穿,两极电阻为300欧姆左右,导致功放供电只有5V左右.如现场无AO4403，也可以把此场效应管去掉用

2、导线接通18V备用应急。也有一小部分无伴音是因为功放U503（MAX9704）假焊造成。机型：LCD37K72故障现象：不开机(灯不亮)检修过程:从故障现象看是无5V输出,先检查F1,BD901,D901发现只有F1损坏,此机5V为LD7575控制输出,检查IC905和Q900，发现这两个元件均损坏,又量了IC905周围元件没发现有异常,怀疑负载有问题,对 D924,D921,IC911,SCR901,IC904,IC912进行测量发现IC911和SCR901已损坏,把这些损坏的元件全部进行更换再检测无问题后开机,5V输出正常,故障解决.维修总结:此故障在这种机型中很常见,更换坏件时需全部进行

3、更换检测,否则又会烧坏.另外此电源部分的Q914很容易损坏,此三极管控制VCC1向VCC2(PFCIC5500)供电的,当主板产生的PS信号后,此三极管导通,此三极管经常软击穿,造成输出24V输出波动.R94947 1/4WR9561K 1/8WR91047+C938100uF/50VC9040.047UFD902FMX-G26SR900447 1/4WR9703K 1/8W+C947470uF/25VCN9031234567891011121314R960NCC9281uFD936FR103+C9812200uF/35VQ971STP20NM50/FP213D977LL4148+5VR953

4、47 1/4WR901951K 1/8WL90310mH1243D973LL4148+C93710uF/50V+C9822200uF/35VVCCL9313.5uH+24VR946470 1/8WIC931LD7522PS12345678BNOCOMP(-)LATCHCSGNDOUTVCCOVPR9180.15 3WR9885.1K 1/4WR905NCC9481000PFC971220pFR9341K 1/8WR98333 1/8WC9841uFNR901NTCR+C9461000uF/25VR900747 1/4WC9531uFQ904KTB1124BD960SSM54PTD932FR10

5、3C914NCC9941000PFR9112.2R9732M 1/4WR90101M 1% 1/4WD9791N4148C9171000pFC9961uFR94747 1/4WR98133 1/8W+12VR900247 1/4WC9730.1uF/50VC909470pF/250VR9942.7K 1/8WR920470 1/4WR90201K 1/8WR9852.0KR9981K 1/8WR91210 1/8WC9290.001uFR900951 1/4WC908470pF/250VC9765600PFR9190.15 3W+5VR900347 1/4WQ972STP20NM50/FP21

6、3+C952470uF/16VR9896.2K 1/8WC9330.01uFIC973AZ431AZ-AE1C9780.1uF/50VD937BA159GPTR9742MQ905PMBS3904VCCR984100K 1/8WQ9732N3904S-RTK/PSR95833K 1/8WR97610KR997150K 1/4WR9251M 1/4WCN901CONN123R9241.5M 1/4WR900647 1/4WR982100K 1/8WR90163K 1/8WR96820K 1/8WC9951000PFCN902CONN123456789101112Q932KTD1691R95447

7、1/4WZD932RLZ15B12D904LL4148R91522 1/8WC9071uF/450VR9710.1 ohm+C97510uF/50VR9931K 1/8WR94010K 1/8WR9612.4K 1/8W-+BD901D10XB602134D978LL4148R9014150K 1% 1/8WC9410.1uF/50VIC972PC123X8YFZOF1243R90111M 1% 1/4WQ931FQPF7N65CC940NCC9740.0047uFC926NAQ9332N3904S-RTK/PSIC971L6599D12345678910111213141516CssDELA

8、YCFRFminSTBYISENLINEDIS PFC_STOPGNDLVGVccN.C.OUTHVGVBOOTC9110.1uFC990NAR9860.68 3WC9800.027uF/1000VR966100K 1/4W24V1C9390.0022uF/1KVR99910K 1/8WR93922 1/8WR9641M 1/8WR900847 1/4WR95247 1/4WR900547 1/4WR95047 1/4WC9970.1uF/50VIC932PC123X8YFZOF1243R92239K 1/8WR901330K 1/4WC9341000pFR978510K 1/8WR9621K

9、 1/8WC9433300PF/50V+C9501000uF/16VR9261M 1/4WR97518K 1/8WC9921000PFL96020uHC9870.1uF/50VIC934PC123X8YFZOF1243R94847 1/4WC9100.01uF/500VR908220K 1/8WR96310K 1/8WD950FME-210B123Q902STW20NM60213R95710K 1/8W+C93247uF/50VE377CZNK2WAEN2GBMHCustom22Tuesday, April 17, 2007715T2512-202.POWERT2512-1-X-X-3-070

10、417OEM MODELSizeRevDateSheetofTPV MODELPCB NAME称爹T P V ( Top Victory Electronics Co . , Ltd. )Key Component絬 隔 瓜 絪 腹+C9831000uF/35V+C918100uF 450V+C91247uF/50VC9931000PFD975FME-220A123R90214.7K 1/8WR90121M 1% 1/4W+C954470uF/25VC9061uFF9020 1/4WC9010.047UFQ903KTD1624C+C99810uF/50VC91356pF+24VR9911K 1

11、/8WD976FME-220A123R90180 1/4WR900147 1/4WC9301500PF/50VR9593.6K 1/8W+C922470uF/35V+C919100uF 450VIC960TPS40200DR12345678RCSSCOMPFBGNDGDRVISNSVDDR9424.7 1/4WR92351K 1/8WC9150.047uF24V24VR97727K 1/8WR91610K 1/8W+12VD971LL4148C9453300PF/50VD972LL4148T931POWER XFMR12356789101112R91410 1/8WL9713.0uH +-10

12、%L901L1243R995150K 1/4WR91710K 1/8WZD931PTZ9.1B12R996150K 1/4WC9770.1uF/50VC9310.1uFC9720.22uF/25VR965100K 1/8WD951FME-220A123C9860.1uF/50VR955470 1/4WD903LL4148Q960AO441112348765SSSGDDDDR9903.3K 1/8WR96722 1/4WC9270.0047uFR90915K 1/8WR906NCC9443300PF/50VCN9041234567891011121314R904NCC9160.33uFZD933

13、RLZ27B12C9050.0022uF/250VVCCT971POWER XFMR67891011131434C9990.01uFR99224K 1/8WPS OND974LL4148R90756K 1/8WIC901FAN7529MX12345678INVCOMPMOTCSZCDGNDOUTVCCR91322 1/8WR9310.1 ohmR9013240K 1% 1/8WRV90156012C923470pF/50VD931LL4148R902330K 1/4WF901FUSEL906168uH12121156C9421uFR9450.47 2W24V1R902222 1/8WQ901S

14、TW20NM60213C9790.1uF/50VR941100K 2WR90173K 1/8WC9240.47uF/25V+C9511000uF/16VL90210mH1243+15VR901562K/0805R9722M 1/4WR95147 1/4WC9491000PFR9270 1/4WZD934RLZ18B12IC933AZ431AZ-AE1R903330K 1/4WR979100C935100n/0805R9875.1K 1/4WC9210.1uFR9803.9K+15VR92110K 1/8WL9323.5uH+C920100uF 450VR96962K 1/8WPS ON 机型机

15、型:LCD42E75 故障故障1:不开机不开机(灯不亮灯不亮)不加电NG重插接口OK检查 F901, BD901, D902NG更换 F901或者 BD901或者D902OKCheck the load检查IC931, Q931 ，Q932 (VCC)NG更换IC931或者Q931或者Q932OK检测IC901，Q903，Q904NG更换IC901或者Q903或者Q904OK检查T931NG更换T931OK检查D950, D951，ZD931更换D950, D951， ZD931NG检测电源接口OK检查L931，L932更换L931，L932NG机型机型:LCD42E75 故障故障2:无显示无

16、显示 (LED 绿色绿色)检查信号源OK重接信号源NG检查LVDSNG更换LVDSOK检查24V 供电NG检测IC971，Q971，Q972OKOK检查U305NG更换U305OKOK检查panelNG更换 panel检查主板供电检查 I2C 通信NG更换IC971，Q971，Q972OK检测T971NG更换T971OK检测D975，D976NG更换D975，D976OK检查 U300NG更换U300 机型机型:LCD42E75 故障故障3: 无显示无显示(灯橙色灯橙色)换按键板检查主板Standby供电更换U702，U703，U700，U704，U705，U706检查 Power_on 信号检查 按键板换 I2C 通信元件无画OKOKNGNG更换Q702，Q703，Q707检查U305NG更换U305OK检查 I2C 通信OK检查 U300NG更换U300NGOKNG机型:LCD32K72故障:无24伏输出(下面 寄上来修的电源