Have a dell DE 173 FPC LCD monitor. When power switch is pushed, the green light comes on then goes off. I replaced a defective 3.3 volt regulator on the small circuitr board. If I have the 4 plugs...
hi, i repair these monitors regularly, capacitors you test, are they close to a block of transistors? the four plugs you speak of are the backlamp connectors. two things, the backlamps could be shorted due to rubbed wire insulation near where they disappear into the screen. second, more likely cause. the block of trasnsitors right next to the high voltage plugs. they are NPN power transistors. it's been so long, but i think they are labeled C5404, don't quote me on that, but they are likey bad and what maybe causing the funny readings on the capacitors. i have never purchased an oscilliscope to test properly, but the DMM ohm readings should show about 3.5 K ohms from end terminal to end terminal(three pin transistors, outside pins, both) when i found ones that were not high in resistance, i junked em. but be careful to only test the one labeled beginning with C, if you find other transistors on the board away from the high voltage block, they are not the same, likely mosfet PNP type and if you test, you may short with DMM. don't worry about capacitors ohm reading, only if they have blown tops of course. most of the time, if i really suspect a bad cap., and if it doesn't have blown top, i will charge with 12 volt power and then check draw resistance dicharging to ground with ohm meter. good luck, hope i helped some.
×