Iiyama b2475hds died.

[khorne55]

Re: Iiyama b2475hds died.

voltage regulators on logic board

903T63 - 5.16v, 3.29v, 0v
1117-18 - fluctuating between 4.72-5.13v, 1.79v, 0v

[stj]

Re: Iiyama b2475hds died.

you need to find out where that defective 5v supply comes from that's feeding the 1117

[khorne55]

Re: Iiyama b2475hds died.

@stj That is a tough task but Ill do my best

[khorne55]

Re: Iiyama b2475hds died.

At one of the capacitors the voltage is fluctuating between 2 and 5v

[khorne55]

Re: Iiyama b2475hds died.

I have circled the bad capacitor also I noticed that one of the legs on the voltage regulator is missing ? At least it seems like it.

[lexwalker]

Re: Iiyama b2475hds died.

voltage regulators on logic board

903T63 - 5.16v, 3.29v, 0v
1117-18 - fluctuating between 4.72-5.13v, 1.79v, 0v

At one of the capacitors the voltage is fluctuating between 2 and 5v

I have circled the bad capacitor also I noticed that one of the legs on the voltage regulator is missing ? At least it seems like it.

Jot down that capacitor value and order a replacement just in case. Is there any inductor and/or resistor before that capacitor? From the looks of things, first have to make sure the +5V rail is stable by replacing those Lelon capacitors on the power supply board. There could be ripples that the meter did not detect (will show as average RMS voltage). Then check again if there is still voltage fluctuations at this capacitor. You could also simply replace that capacitor just to test...

[khorne55]

Re: Iiyama b2475hds died.

@lexwalker the 5v rail is 100% stable coming into the logic board however the dim line is fluctuating from 0.33v - 3.3v.

[stj]

Re: Iiyama b2475hds died.

replace the cap, and about the regulator - the missing center pin is connected to the tab that is soldered down - so no problem there.

[khorne55]

Re: Iiyama b2475hds died.

This ia the cap I will be getting as replacement,
EKZE100ELL221MF11D
CAP 220UF 10V ELECT KZE RAD

[khorne55]

Re: Iiyama b2475hds died.

Ordered all of the caps should have them within a week as the warehouse in my town needs to import them.

[selldoor]

Re: Iiyama b2475hds died.

OK kze should be good assuming you have correct uf and v
Im still not sure its going to fix it though
Did you try it with vga input. nad did you do any tests on
the LED strings/driver circuit.

[khorne55]

Re: Iiyama b2475hds died.

I did not since there is no power in the monitor anyways.

If by the driver circuit you mean the the second board(logic) yes I did carry out tests there, everything seems fine except for the fact that there is the fluctuating current in there at one of the pins of the voltage regulator.

[selldoor]

Re: Iiyama b2475hds died.

OK - I was reading this
http://forum.hardware.fr/hfr/Hardwar...et_57492_1.htm

No I meant the circuit that light up the screen - LED light

[khorne55]

Re: Iiyama b2475hds died.

Interesting similar problem except with the outputs, luckily he had warranty.

[JD714]

Re: Iiyama b2475hds died.

Hey,
I have opened the monitor up

Hi,

I've got the same monitor which died too, after 3 years only...
I'm trying to open it up, but I didn't figure how to do so, at least without breaking something. Any help to remove the case would be very welcome!

Thanks in advance,

[Elri]

Re: Iiyama b2475hds died.

Hello,
I've exactly the same problem on the same monitor : all voltages (5, 3.3 and 1.8V) are ok, all capacitors seems to be ok but the can seems to permanantly reboot. Maybe like if a watchdog retstart the microcontroller...
When rebooting, all voltages are stable (with oscilliscope) but an inrush current occurs at each start up.
Seems like firmware is currupted... I'll try to replace quartz but without conviction.
Did you manage to repare your screen ?
Thank you,

[selldoor]

Re: Iiyama b2475hds died.

Please post pictures of both sides of your boards

[Elri]

Re: Iiyama b2475hds died.

In fact it is exactly the same pictures as at the begining of this posy, with ALL same behaviour ( including dim pin ). Did the previous member find a solution ?

[killeroid15]

Re: Iiyama b2475hds died.

Hey guys, I think i have the same problems as i didn't opened up the display, i bought it from someone and the first day to test it already died .... just factory reset the display and then i turned off, after that wouldn't turn on again, and no lights as well, I've pulled out the power cord then back again but nothing...
Did anyone KHRONE55; JD714 or ELRI found a solution ?
Thanx

[chaos_prevails]

Re: Iiyama b2475hds died.

hello,
has somebody an update?

I found this http://www.elektroda.pl/rtvforum/topic2353592.html suggesting that the Novatek Chip has to be replaced.

I have the same problem and if the chip is broken, I would need the whole video board (I don't have the tools to solder SMDs). But I don't find anyplace where to buy the video board