Hi all. About a year a go I had the same problem with another monitor but never managed to solve it.
No here's one more of these at my desk.
Problem is the same, backlight is off, picture is there (tested with the flashlight), but this time i have wee bit more experience, and a better camera
So, there were 3 bulging caps and i replaced them all (with 1000uf instead of 820, but I have put 2x1000 and 1x470. Thing I have done many times, including few displays I still use, and it works). Rest of the caps look ok, but if needed i will replace them.
edit: I also replaced 2x1000uf 10v with 1000uf 16v (blue ones) that are salvaged capacitor from the device that worked but was useless)
It's a bit hard to find right capacitance and voltage combinations for the smaller ones, but i'll manage if needed.
So, connector that connects digital board and PCB has ON/OFF, DIM, 5.1v x2, GNDx3, 13v x 1, DIM.
I tested 5.1v and it's ok. But 13v is somewhere around 19v. Along the way on the CB I found one zener diode, tested it and it's OK. Rest of the line goes to 3 capacitors I replaces, few resistors (none are black, bulged or exploded), and a fuse that also looks OK.
Last time there was something about testing MOSFETS U202 and U203, but I can't remember the procedure. Mosfet labels are 4502C and both have 8 legs (4 of each side).
So here are photos of the PCB, as digital board is working (picture is there, with no disturbances as far as I could see).
No here's one more of these at my desk.
Problem is the same, backlight is off, picture is there (tested with the flashlight), but this time i have wee bit more experience, and a better camera
So, there were 3 bulging caps and i replaced them all (with 1000uf instead of 820, but I have put 2x1000 and 1x470. Thing I have done many times, including few displays I still use, and it works). Rest of the caps look ok, but if needed i will replace them.
edit: I also replaced 2x1000uf 10v with 1000uf 16v (blue ones) that are salvaged capacitor from the device that worked but was useless)
It's a bit hard to find right capacitance and voltage combinations for the smaller ones, but i'll manage if needed.
So, connector that connects digital board and PCB has ON/OFF, DIM, 5.1v x2, GNDx3, 13v x 1, DIM.
I tested 5.1v and it's ok. But 13v is somewhere around 19v. Along the way on the CB I found one zener diode, tested it and it's OK. Rest of the line goes to 3 capacitors I replaces, few resistors (none are black, bulged or exploded), and a fuse that also looks OK.
Last time there was something about testing MOSFETS U202 and U203, but I can't remember the procedure. Mosfet labels are 4502C and both have 8 legs (4 of each side).
So here are photos of the PCB, as digital board is working (picture is there, with no disturbances as far as I could see).
Attached Files
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