EIZO CX270 - No signal but Backlight and Panel works, logo works, admin menu works. OSD doesn't. What?!

[vf fa]

Hi, so i guess I´ll have to make a new topic here, as i browsed through hundreds of other threads but couldn't find a solution to my problem yet.

I got a EIZO CX270 from a friend. He said it doesn't work anymore and wont display any signal or take any OSD inputs. Well, as an aspiring photographer I couldn't say no, could I? Thought it was an easy game, replace a bad cap and have a working monitor. But nooope, it wasn't supposed to be this easy.

So let me start with the problem description. I'll try my best not to skip anything so this might get rather long.

The patient presented himself as a very clean, almost new looking monitor (even though it has 63.000 hours of on-time!). There are no marks, dents, scratches etc.
After plugging the power cord and Displayport cable in the Power LED flashes 4 x orange and 1 x blue. After pressing it again, the Backlight powered on and a EIZO Logo appeared (no distortion and fading etc. Clean image).


After that, nothing happens. No button pressing seems to do anything. Only the power button works without fail.
Trying to access the "Admin Menu" (holding Mode while powering on) gives me the admin menu. So the buttons do work after all. From here I can't do much though.

I then ofc tried various cables, ports, output devices, settings etc. But no luck. Thus, I decided to take a look at the main board and T-Con to see if there were any blown caps or burning marks, fuses etc.
But to my horror, it looked pristine. Damn.

After my first visual inspection I reseated the LVDS cables (for right screen side) but accidentally forgot to turn the thing off. As expected, the right half of the screen went white. Unexpectedly though, the left half now displayed a message: "no signal".
Nice! I pressed "enter" and was now able to access the menu. Turns out the menu isn't very useful if you only see half of it. But i was still able to reset to factory settings.

Turning the Monitor off again, I started pondering wether the LVDS was defective (or something creating a short before or after LVDS for the right panel side).
But I found absolutely nothing. Everything seems to be in perfect condition. I looked for cold solders but again, found nothing.

So I went ahead took out all PCBs, unplugged all the cables, inspected them, took a few measurements and plugged everything back in, though half disassembled.

I didn't have any hope, but I turned it on anyways. And holy bananas - we have contact! I got a perfectly fine 2560x1440p image output from my PC, displayed on the monitor, no artifacts, no fading, no weird gamma, just a perfect picture.

So, i thought I might have accidentally fixed the problem. I turned it off, assembled it almost fully aaaaaaand, got a no signal input message upon powering it back on.
Sure thing, just turn it off and on to see if that helps - well, nope. I am back at the start with the 4x orange 1x blue power led code and no messages or OSD.

Messaged Eizo support and asked what 4xorange 1xblue meant and they told me that they didn't have the slightest clue as that was nowhere to be found in the service manuals. They do however have 4 x blue 1x orange meaning "bad Displayport unit" but other than that have no idea as to what might be going on.

So I am turning to you, great hive mind of badcaps forums.
Maybe someone has any idea as to what might be the problem here?

I do study Communications-IT (everything from Chip design to coding and electrical engineering) but without schematics I am not really confident or experienced enough to make a good guess.
I have a good soldering station, a few multimeters, amp-meters, microscope but no oscilloscope (yet).

Thanks in advance. Any help is greatly appreciated.
I'll try uploading high res images of all the boards soon.

Cheers.

[vf fa]

*Added images

[vf fa]

Okay. So I might be going bananas, but im sure this monitor is out to troll me.

I took a lot of measurements and reading on all kinds of SMDs, ports, wires etc. Then, i wanted to take some other readings, while powered on... and god damnit - it powered on just fine. With everything plugged in. And its been running non Stop for around 4 hours now. There are no artifacts or distortions of any kind. It happily displays all test patterns and works using both HDMI and Displayport.
Now, i am afraid to turn it off again. Because the last time it did that, it didnt wanna power back on. Im not sure what to make of this. It seems like the monitor heating up, causes it to fail the POST (power on, self test), but doesnt keep it from running continuously. This is all very confusing. What i do notice however, is that the CCFL backlight is not very bright. Or at least, raising the brightness slider to above 136cd make the number go red (meaning its not within reach). Checkd with my FF Sony Alpha 7R3 on manual, and yup, its not getting brighter after ~130cd/m². If i am actually able to fix this thing (whatever the problem might be), i might be able to replace the 8pc U shapce CCFL backlight. But i should focus on finding out whats wrong first.
Sadly, EIZO support told me that they are not allowed to send me schematics or the service manual.

So. While writing this, i am going to turn the monitor off and back on, and see what will happen.

* insert time skip here *

Damnit.
Well. It worked again after pressing the power button again. Then it didnt, after i unplugged the power and plugged it back in. Well, it does work, i can even access the OSD menu, but its not recognizing any input. Damnit. So i guess its not the T-con then.
Next step is removing the Mainboard and desoldering all the caps in order to test them. After that is going over most solder points and systematically check all caps and resistors between the inputs and the Xilinx FPGA and both Eizo ASICS.

Hopefully ill have some results to show, when im done. Wish me luck - if anyone even reads these.

[CapLeaker]

Took me a while to read it all. Seems like this monitor has an intermittent. If it is a cap problem, the monitor should be having a problem with cold, not when warm. That.leaves 2 more choices, Either an IC is defect as the can clink out when it's warm, or there is a cold solder joint / broken trace / bad BGA / broken HDMI port somewhere. I also did see 2 winbond flashes…
Nice thing about Eizo is they actually label their test points. So you can take readings and note them down working vs non working. Seems like in your last post, the OSD and all that jazz is working just no input.
So go backwards then from the HDMI port to the HDMI switching IC. Heat it up a bit with wifey's hair dryer, or freeze it with a can of air (duster) held upside down, put pressure on chips or the PCB. I am not familiar with that model, but maybe try a different input, like VGA or a display port or a second HDMI port etc. 65000 hrs is quite a bit, I really can't imagine them being the original backlights. They should be kind of having a pinkish hue by now.
caps can look brand new like, but yet be bad.

[vf fa]

Thanks for taking the time to read, I really appreciate it.

I guess calling it an intermittent would be quite fitting. I suppose it mostly works when cold. Also seems to mostly work when it has either been turned off for some time, or restarted within 5 seconds of being turned on (where about 90% of times the restart fails if I wait longer than 5-10 second after turning it off). It's certainly odd.

So, I went and checked almost every trace between IO and LVDS cables with floodlight LED under the PCB, through a microscope. Seems like those are good, both in cold and warm conditions. Then pulled all the caps, one after another and measured them. They all are within 3-5% of rated capacity (ofc only the ones that have something written on them - the other small SMD types I have no way of telling)

All resistors and diodes seem to be as expected/labeled.
I created a Excel sheet of readings on the probe points, but I am not home RN and didn't have time to transfer the sheet. I'll do that tomorrow.

I did try putting pressure on the ICs, aswell as cooling them via reversed air can. Didn't seem to change much, or anything at all.
Heating the Board with a Hairdryer did result in acutely increased chance of failing to start. Up to a point where it was impossible to get a OSD menu (other than the admin menu, which always works and so far always has worked since I got the monitor).
But it worked again after cooling down a little (I did try the reverse can cooling 'RCC™' during this phase, but it doesn't seem to have an effect when applied to the larger ICs).

This, and the fact that it appears that the monitors function is only inhibited during startup (POST?), makes me Believe that it's the EEPROM (or any of the other flash chips). I did resolder those, just to make sure it's not a nearly invisible cold solder, but this didn't change too much. I fell like it has improved the average amount of good starts, but it does still consistently fail in about 50% of cases, especially when even slightly warmed up.

Maybe the EEPROM is reaching eol. Due to the fact that it is indeed still working, sometimes, I will try extracting the contents from those, if possible. Maybe I can get my hands on a replacement EEPRom chip and reflash the dump there. Worth a shot, and honestly I do enjoy this kind of tinkering. Would just be cool if me failing wouldn't kill the main word for good.
I thought about using my RaspberryPi for this, but this seems to be a rather wonky solution, and seeing as an M24Q64 reader/flasher is only 15€ on amazon, I ordered one of those. Can still use the raspi if that thing doesn't work.
Just gotta be really careful as to not overwrite or erase the data that is stored on there. Found this Github repo that should work, but I haven't fully gotten around how to actually use it. It seems to want to execute all available functions at once, which isn't exactly ideal. Luckily I didn't connect any leads yet.

Again, thanks for taking the time to read my, rather lengthy texts. And thanks for your help. I truly appreciate it.

Cheers

[CapLeaker]

To check the winbond chips or any SPI or eeprom, read it a couple of times and make sure the data you pulled is the same (compare). Then erase the chip by FF'ing it. Read it again for everything is being FFed or blank check. If all is good, there isn't anything wrong with it.
So heat makes the monitor quit more likely than cold. Really points to an IC of some sort to me. Remember IC's can clunk out even after 15 mins of running. Hopefully you can find the culprit by cooling and thus extending the time or heating cutting the time short.
I've had about a 75% success rate of reviving token eeproms of a last read by freezing it with the upside down. Have to think about this a bit more.

[vf fa]

Okay, so I apparently didn't save the Excel sheet where I noted all the voltages - but I don't think it matters anyways, as I couldn't make out any weird readings (except for two voltage regulators that have their output side immediately connected to ground which is kinda confusing to me - next to the Fan connectors.).

But today the EEPRom 24/25 reader arrived. Before I had to leave for the day, I was able to get it running and took 4 readings of the FPGA M25Q64CVSIG, aswell as 2 readings from the M25Q16CVSIG that sit next toy the Eizo LVDS chips each.

The Eizo chip EEPRom checked out fine, the different readings were identical to each other and "Verify IC" checked out fine.
Then I compared the 4 readings from the FPGA EEPRom and all 4 were different. When trying to verify the IC, I got errors in different Addresses each time. I reseated the reader but still same result. I'll verify again tomorrow (and could possibly dump the contents from all 24 and 25 series chips If allowed).

But to meet it looks like the EEPROM for fpga is faulty. Just need to find a replacement chip if it really is. And ofc I would need to get a non faulty reading and verification. Possibly trying that again with the chip cooled down.
Should mention though that I did not remove the chip from the board for reading, but power was unplugged and caps discharged.

Cheers

[CapLeaker]

interesting. 4 reads, 4 different readings off the chip. As long as you did the readings back to back without powering and changing something, I suggest the eeprom is bad. Weird, that you got errors on different addresses each time... can you post the 4 different dumps?

[lotas]

If you read the data through a clothespin without unsoldering the eeprom chips themselves, then there may be discrepancies like this (you must always unsolder and clean the contacts through the adapter to the programmer).

[vf fa]

Yeah, a bit weird. I was in a bit of a rush, so I'll verify again. Iotas Is probably right, that might make a difference. I'll double check tomorrow and unsolder the EEPROM to read without interference. I should not however that the ones from the Eizo chips (the ones I called lvds) were identical both times and verified on first try.

Cant upload the dumps here, so Google drive it is: LINK

Just noticed file says 25Q56 instead of 25Q64, don't get confused, that was a typo.

[vf fa]

Update: Testes the eeprom after desoldering. Now verifies and readings seem to be identical. Well, there goes that theory.
Pasted the dumps, had to rename them to .txt otherwise .bin was not allowed for upload. Hope this is okay, if not, ill remove them ofc.

[lotas]

Bin files must be packaged in WinRar or Zip.

[CapLeaker]

well, so here goes that theory.... If you want to verify the integrity of the flash, make sure you have consistent readings, save the file, then do an erase followed by a blank check, If all is good, copy the content back on the chip. I still feel like the problem is an IC of some sort, a cold solder joint or something along that line.

[vf fa]

Yea, i guess that would have been too convenient. Idk why i jumped on the eeproms so quick. Would have maybe made sense for a failed/corrupt POST but yea. I´ll post the entire dump here though.
Im gonna go back to testing the Chip. Might take a look at the T-con again too. The symptoms of a full "on but not working at all" are pretty much consistent with disconnecting the LVDS (1). So i´ll go ahead and give it the "cool - hot - cool - hot" test. Then FPGA and then T-Con chip. I´ll get back to you if i find/suspect anything.
If it really is any of the BGA chips, im pretty much out of options. I dont think i have a way of reballing/reflowing or reworking those.

Dumps:

[CapLeaker]

as long as the OSD works, the LVDS and the tcon are fine. It leaves anything between the HDMI port over to the HDMI switching IC to the processor.

[vf fa]

Well. You are right. Can't be the LVDS if the admin menu works.
But it's not just the HDMI, Displayport doesn't work either. If "the problem" occurs - then both HDMi and Displayport won't work, the osd won't work, the admin osd menu does work. That indeed rules out the LVDS. But I feel like it should also rule out the HDMI and DP chip, as those are separate and its unlikely that they both fail at the same time, every time (unless one fails and triggers a fail state or the power delivery fails - which I thought I had tested).
So that would leave me with fewer points of failure.
might be the FPGA, but neither cooling, heating, nor pressing down on it seems to be making a difference. Let's just hope it's not the FPGA for now.

Other options include: Renesas M16C Microcontroller (U8001), or the other Renesas Microcontroller which says D78F1168 and should be a 70K0R/KG3 with 512kB rom and 30kB ram. (U7000) and maybe U8803 although I can't tell what that thing does.

The M16C and especially the 70K0R have a lot of interesting test point descriptions like TconOn, fpga on etc. So I guess a failure on a pin there would pretty much explain the behavior. Furthermore it's not a BGA, so I could actually to a proper check for the contacts and supposed signals (and there is no way for me to know how the FPGA is programmed)

Wish me luck.

[lotas]

First you need to check the supply voltages on the dc/dc converters, ripple, maybe something is leaking and providing unstable power...

[CapLeaker]

I agree with lotas. That would be the next logical step to do. Verify all the little dc to dc converters first.

[vf fa]

These are the DC measurements. I've just startet AC measurements while writing this, but I already have 0-87V AC on the Power Input pins 10-13. Seems to be gone after the 12v and 14v caps (havent probed everything on AC yet) but I can't imagine that this is how it was intended.

Should mention though, that the screen has been working flawlessly the entire day, giving me pictures on both HDMi and DP. Even heat treating it doesn't make a difference. So all measurements so far have been done with the monitor fully working. But I don't think that I have magically solved the issue by reading and verifying the Eeproms. It's really confusing. I can't even get it to "not work" - as stupid as that sounds. I shall continue trying though.

[lotas]

Possibly due to warming up (dismantling, installation) Spi flash, eeprom - performance has been restored in the buggy chip.
If the problem appears again, try writing your dumps to new chips.