Monitor diagram Pls help me find good resource in schematic diagram of LG910B monitor (shorted 19N20C transistor surrounded with 4 burnt unrecognizable resistor's value) and Samsung SyncMaster 551V with DP704C power transistor (no power; good primary components and secondary components; want to check shutdwon circuit and standby voltage ckt and feedback voltage as well). Many thanks. Rosener or www.surigao-csc.com

This website appears to have diagram for it. You will have to register to log in. http://elektrotanya.com/?q=hu/content/how-change-site-language-english
May of been some other component burnt out. Only way is by test meter and testing. Quite possible transistor burnt out.
You should be able to test it in circuit for Short circuits.
If output transistors faulty make sure you check driver transistors as well. Hope some of that helps.

The resistance is heating up as there is very large current flowing through it. Hence the feed of the resistance circuit must be checked as there is a SHORT in this circuit.
A test with a multimeter will confirm the shorted component, de-solder and check with the resistance connected back to confirm the fault. Check the +B voltage to be steady before the components are put into the board..

change the board

Hi,

Initially, pls check D854 on the Power Supply/Logic board. It is a dual diode. If you would prefer board replacement rather than component level repair, this might be of help. This of course would require a fair familiarity of electronic components/circuitry and safety procedures, use of a DVM and a soldering iron. It would be to your added advantage access to a service manual or at the very least a schematic diagram with voltage readings. Should you be uncomfortable performing a DIY (do-it-yourself), perhaps your best bet would then be to seek the services of a qualified professional.

This is of course in addition to checking the usual, power cord, fuse, outlet etc.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information. Good luck and kind regards. Thank you for using FixYa.

Hi...there,
No, power.. Could one things, your backlight inverter are burnt out. Need to replaced a new inverter or repaired it.

You have something in short circuit in power supply pattern, so filter coils are burnt. It may be voltage regulator, or regulating transistor, electrolytic capacitor or even shorted diode at pwr. input serving to protect in case of inverse polarity applied. Check all for short. Was it reverse polarity or overvoltage occured?

Mladen,
[email protected]

first of all you should check power cable of smps. if it is ok then you can check smps for ok or fault.Short green and black wire in main output connector(for motherboard).If fan dont moves then check primery rectifire(4 diodes),switching transistor and protestion transistor(on first heatsink),check fuse,ntc,capacitorin primary section. Hope this be of initial help/idea. Pls post back as requested, how things turned up or should you need additional information.
Good luck and kind regards.
Thank you for using FIXYA.

i have the schematic on this board if you would like to send me a email ill send it to you..