Acer FP588 15" lcd mon. no video

[Davi.p]

This is lcd that i bought dead hoping to repair it easily like another i had before, but i'm unsure, when i push on it stays green with led and no image no b.light, i notice a bit of activity on the screen only when i sw. off infact it has no dark image but there i see a rapid 'white' screen (with lamps off), i opened it and found to the right in zone of inverter card a little sign of dried liquid and a corrosion on a screw, sob!.. apart this the inverter has any sign
of liquid passing, the voltage come to this board, 12, 5 and 1,4 v, i suspect a problem in the video card, infact psu work well, in that instead there is a white smd fuse that has no potential on its terminals, fuse ok, it go to the panel connector, probably to power it, on the other side of the fuse, before it, a 8pin sop smd chip that has 4 pin in a row connected together, 3 other in a row together and 1 lonely, seems a mosfet, it has on the gate approx 5v and the 'maybe' source (3 pins) also 5v, in drain approx 3v that go down whenever i test it. I wanted to know how to force the b.light on to test it,
i know 2 wires are 12v (together) , 2 are 5v (but separated), 1 is gnd and 1 is at 1,4v, one of the 5v is for the logic i think, 1 is maybe b.l.on ? the 1,4v i don't know but maybe brightness? On the inverter the fuse is ok and the 2 lamps out are 0v, apart this test can i do some other tests, like bypass/bridge the 'mosfet' (don't find info on it) to maybe force to power up the panel? Thanks very much.

[Davi.p]

Re: Acer FP588 15" lcd mon. no video

Sorry, i've made many grammatical errors..

[Dgtech]

Re: Acer FP588 15" lcd mon. no video

I hope you didnt pay much for this LCD just to find out there was corrosion inside. This repair doesnt even sound cost effective unless you are doing it for the education, then it's worth something. If you can take some good clear pictures of the boards, post them, then maybe someone can help. Personally, I've had a few Dells where I work that had coffee spilled on the bottom of the screen that screwed up the lamps/terminals.

[Davi.p]

Re: Acer FP588 15" lcd mon. no video

I have spent few moneys, i have made some pictures not much clear but if i get closer them goes out of focus, made by cellular, in the inverter there is no sign of water/burnt damage, i have made 2 tests, in inverter picture i've put that little pieces of white tape to make a bridge with a wire, first 3,3v from psu then 5v from connector itself (short to near pin) to the 1,4v pin that i hope was the b.l.on signal to powerup the b.light, no result.. then i've made a short with that little white wire in v.board back picture right low corner, on the suspected mosfet, from maybe source to drain, to power up the panel that before was not power supplied (no V in 'maybe' Vin pins), no image appears... but now the screen seems more black when 'on'.. it's all
for now, thanks, and bye bye..

[Davi.p]

Re: Acer FP588 15" lcd mon. no video

for that 'mosfet' i have found a datasheet with a similar code, so it's much probably a mosfet..

[Davi.p]

Re: Acer FP588 15" lcd mon. no video

Done this other tests, to activate backlight i have shorted to ground the 1,4v in th inverter connector but nothing, i've found there's no pwm chip in this inverter board, i thinked there was one in every inverter.. there is a double mosfet (N+P) chip whose Drain pins are at 12v, there are 2 74hc02d 4-NOR port chips who are correctly supplied
at 5v, there are some sot-23 chips 1A, p06 and 702 who are pnp trans. and N mosfet,
maybe i have to test them but i don't want to remove them for now. There is a little bit of liquid sign on this board in thruth, near a screw.. bye.