Sharp LC-40le540 stuck in standby/not responding

[Dannyx]

Good day folks. I've got this Sharp lc-40le540 which doesn't want to turn on (duuh). The problem is this (exactly the same as this guy, whose method I will attempt soon): plug it in, the blue "V" power light at the front turns on, but the set doesn't respond to the touch-controls or the remote. Sometimes the LED randomly goes off and then comes back on, but that's about it. The first thing I checked was of course the PSU, which I believe is OK: when the TV is first plugged in, it gets its PS-ON signal from the main board right away and all the voltages (except the BL pin) come up, despite the set still being dead. After a little while (sometimes when the soft keys are pressed, though not always) the LED goes off and so does the PSU, including the 5vSB rail, which shouldn't happen, to my mind. However, when I unplug the power supply from the board and turn it on manually by applying 5Vsb to PS-ON, it holds the voltages up just fine and even the backlight turns on when I tie the BL_ON pin to 5v as well. To confirm it's not the PSU that's the issue, I took an ATX power supply with stripped wires, connected the 5 and 12v wires to their respective locations on the power connector and plugged the thing in: the power supply didn't stall to indicate a short, but the TV did the same thing: the blue LED would go on and off and nothing else. It's definitely a faulty main board, I thought to myself, which would've been the end of the story, had it not been for my boss who insisted that I search for a replacement board which he agreed to pay himself...."Fine, I said, but don't come crying to me if it still doesn't work" (this is why I never tend to replace boards unless I'm absolutely sure it fixes the issue) so I managed to find one that was the exact same model (though from a larger TV), it arrived today, I installed it and big surprise it STILL doesn't work. Wish I had come across the guy's article earlier, as it's apparently a firmware issue and BOTH boards seem to suffer from it (despite the bastard who sold it to my boss claiming it's ok). The problem now, assuming I manage to turn it on in service mode, is getting the firmware. I got the service manual and will try looking through it, but perhaps someone else had this issue and can come with some suggestions. Cheers.

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

UPDATE: I tried starting in service mode and amazingly it worked, though just as the writer of the article said, once I switch it off, it won't come back on normally - I have to go in service mode. I'm not sure whether I can find an update for it, as the guy doesn't say where he got his. Perhaps I'll try connecting it to the internet and try it that way. There's another thing I noticed, though I believe this is unrelated to the problem at hand: have a look at the picture - notice the dark patch on the right...busted panel ?

[dskall]

Re: Sharp LC-40le540 stuck in standby/not responding

Dark area maybe some failed led's. In the post you referenced in the comments section he says that the german site for that tv has the firmware. http://www.sharp.de/cps/rde/xchg/de/...m?p=LC40LE540E

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Dark area maybe some failed led's

Doubt it, because if you look closely at the OSD in the second picture, there's also some slight distortion of the color and some artefacts - the same thing you'd see if you had a bad gamma IC, except here it's localized in that one area. That's the least of my worries though. Now I've just tried updating the firmware though the network and indeed it found something, but after it went about its business and tried to restart it failed to start back again, so I guess I have to install it by USB...first I have to find it :|

[dskall]

Re: Sharp LC-40le540 stuck in standby/not responding

Did you try link above?

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Did you try link above?

Oh you probably added that later on, as I didn't see it there the first time. I shall try it, see what happens...

[dskall]

Re: Sharp LC-40le540 stuck in standby/not responding

You have to go to german site. http://www.sharp.de/cps/rde/xchg/de/...=1214&os=&emu=

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

You have to go to german site. http://www.sharp.de/cps/rde/xchg/de/...=1214&os=&emu=

Yes, I did that and even got the archive containing the firmware, though I'll have to transfer it to work tomorrow, as that's where the TV actually is

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Just managed to update the firmware of the replacement board, so that's the good news. The bad news however is that, one, we still have that nasty patch of discoloration on the right and two, the original board is now dead - won't even start in service mode. Don't really know what happened to it. It could be my mistake though, because I downloaded the firmware for the original TV (LE540), but I forgot the "new" board I had in the set at the time came from a 730 and although this had no immediate nasty effects (other than getting a "failed" message) it may have eventually bricked the board. Funnily enough, despite trying to flash the wrong firmware twice, the TV still started up in service mode every time, until I realised my mistake and got the correct file ready on the flash drive, only to have the board quit on me All well, at least now I have a partially working set. About that patch of nastiness: it's only visible on color - the whites are perfect, so it's like a gamma IC failure, though that would've affected the whole screen.

[dick_barton]

Re: Sharp LC-40le540 stuck in standby/not responding

Is it possible to program the EEPROM externally using a programmer?

I bought a set with not too dissimilar a fault showing some really weird patterns on the screen. I opened up the panel and there was water between all the sheets mixed with nicotine. All the panels and diffuser sheets had to be given a thorough wash.

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Is it possible to program the EEPROM externally using a programmer?

I bought a set with not too dissimilar a fault showing some really weird patterns on the screen. I opened up the panel and there was water between all the sheets mixed with nicotine. All the panels and diffuser sheets had to be given a thorough wash.

That was most fortunate of you, however my TV displays white perfectly, so I doubt there's any dirt or stains caught in the panel. As for the firmware, I guess in theory it ought to work, however I don't have a programmer available, plus I'm not sure how you go about loading the firmware file onto it. Obviously the TV does it "internally", so I don't know how you'd take the file and emulate that process with just the flash chip alone...I'm not a software guy, I admit.

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Great news: I managed to revive the original board as well. What I did was load the correct firmware on a flash drive, plug it in, the LED at the front began alternating blue-red and as it was doing this it was apparently loading the firmware "blindly", without actually displaying anything. I thought it'd just sit there and do this endlessly, but to my great amazement it fired up eventually....so now I have two working boards, plus a working TV but with a dark patch...not too sure what happens next, but hey: we've learned a pretty expensive lesson: don't throw out the boards until you've exhausted every last possibility

[vinceroger69]

Re: Sharp LC-40le540 stuck in standby/not responding

certainly a odd picture fault are these sets edge lit leds?

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

certainly a odd picture fault are these sets edge lit leds?

I don't think so - haven't taken the panel apart, but I doubt it: the wires seem to lead straight into the chassis rather than the edge.

[dskall]

Re: Sharp LC-40le540 stuck in standby/not responding

Does flexing the panel change anything?

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Does flexing the panel change anything?

No, it doesn't. Pressing on the affected are does cause the picture to change, but all LCD panels do this, plus it doesn't actually SOLVE the issue - my finger or whatever just creates an impression which then fades away, obviously. I'm starting to think it could be a panel issue, because in a previous post of mine where I was trying to fix a Samsung TV which had no picture AT ALL, I mentioned reading a post on another forum where the guy sort-of made the TV work by insulating the VGH pin (which was faulty for some reason) to the T-con. This of course meant that part of the panel no longer "charged", since VG HIGH is what charges the pixels while VG LOW discharges it, producing almost the same result as my set. I was going to grab the photo from there to show it to you for comparison, but the post no longer exists

[kape_bi]

Re: Sharp LC-40le540 stuck in standby/not responding

Thank's guy's, the same problem...!!

[Dannyx]

Re: Sharp LC-40le540 stuck in standby/not responding

Well well well, remember this thread chaps ? Apparently this TV is back at it again: it belonged to a colleague of mine and he told me he's having the same issue recently - TV not turning on. Just stays there with a blue LED. I walked him through basically this whole thread since I myself forgot what I did to get it going, but he said he couldn't do it: couldn't enter service mode with VOL- and INPUT held down. I then tried the USB trick: load the firmware onto a flash drive, plug it in and let the TV do its thing. Indeed his flash drive showed some activity but upon finishing, the TV was still dead...must admit I didn't get so lucky as the first time Anyone got any other tricks or methods they used ? Board may have gone belly-up for good this time. Cheers.