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  • 285. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    Sorry,

    I can't see the spec for it's PSU. The 22" model claims it had a round PSU (like the previous link).

    http://manuals.info.apple.com/en_US/CinemaDisplay_22inchAbout.PDF

     

    I don't know if all displays with ADC connectors only had one input. My really old 17" CRT display with an ADC connector only has one input. Just the display lead is connected. It got all it's power from the Mac, but it did mean that only certain Macs were compatible with it.

     

    There was an ADC to DVI adapter that was used to provide power & the DVI connector for Macs that hac no 28V supply for ADC.

    http://www.vistek.ca/pdfs/207049.pdf

    Is that what you have?

     

    It is not the same as these power supplies discussed on this forum, you may just need an ADC to ADC lead.

     

    Take some photos of the ports in question if you need more help.

  • 286. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    pelachile Level 1 Level 1 (0 points)

    I have a similar problem on a 23" A1082 Cinema Display. However, I don't have any flashing LED. It only flashes when I hold my finger over it and then it doesn't flash a code it just flashes on off on off on off repeatedly. I know the 90W power brick it is not the culprit because my other 23" display works just fine with it. I have tried the PRAM/VRAM thing, the "Jacobean" fix and every other thing short of deleting plist files or using a 150W power brick. The monitor will not work on my Core 2 Duo MBP 3,1 nor on my 2.6 Eight Core Mac Pro 1,1 with an ATI Radeon 5770.

     

    The monitor is definitely recognized as it shows up in display preferences and I can move my mouse into the blank screen as well as switch which display has the tool bar. I am not having a backlight issue as I have put a bright light up to the screen and it is just a black hole. When I put the computer to sleep the LED on the front of the display will light up but when I wake up the computer the light goes out. This happens regardless of which computer it is hooked up too. 

     

    I would like to know if dropping $200 on a 150W power brick would be just throwing good money after bad and I should sell it and buy a different one with the $200 I was going to use on a power brick and whatever I can get for the non-working monitor?

  • 287. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    treehousedaddy Level 1 Level 1 (0 points)

    I eventually bought a second-hand reconditioned 150W power brick on eBay and it solved the problem. Worth it.

  • 288. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    pelachile wrote:

     

    I have a similar problem on a 23" A1082 Cinema Display. However, I don't have any flashing LED. It only flashes when I hold my finger over it and then it doesn't flash a code it just flashes on off on off on off repeatedly. I know the 90W power brick it is not the culprit because my other 23" display works just fine with it. I have tried the PRAM/VRAM thing, the "Jacobean" fix and every other thing short of deleting plist files or using a 150W power brick. The monitor will not work on my Core 2 Duo MBP 3,1 nor on my 2.6 Eight Core Mac Pro 1,1 with an ATI Radeon 5770.

     

    The monitor is definitely recognized as it shows up in display preferences and I can move my mouse into the blank screen as well as switch which display has the tool bar. I am not having a backlight issue as I have put a bright light up to the screen and it is just a black hole. When I put the computer to sleep the LED on the front of the display will light up but when I wake up the computer the light goes out. This happens regardless of which computer it is hooked up too. 

     

    I would like to know if dropping $200 on a 150W power brick would be just throwing good money after bad and I should sell it and buy a different one with the $200 I was going to use on a power brick and whatever I can get for the non-working monitor?

     

    It sounds like it could be a dead panel.

    You will have to search & see the cost of second hand models, personally if I had tried two other power supplies I wouldn't expect a third to be any different. Search these forums for better fitting symptoms, there may be someone that has experienced it too.

     

    FWIW, test it with no other displays connected (if you were using two screens on the Mac Pro) & maybe try a boot from an install DVD to eliminate the OS as part of the issue. Redo the 'torch test' & get up real close to be certain it is not the backlight.

     

    treehousedaddy wrote:

     

    I eventually bought a second-hand reconditioned 150W power brick on eBay and it solved the problem. Worth it.

     

    With respect treehousedaddy, I don't think this is the same problem. There is no error flashing on the status LED, & the way it's described it is working correctly (at least the LED sleep/awake status bit).

  • 289. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    pelachile Level 1 Level 1 (0 points)

    I'm leaning towards the dead panel scenario myself. However, one thing I have noticed is that the power brick is not getting warm at all. I'm not quite sure what that means or if it is even significant. I am thinking that it is not drawing any power through the brick but I wouldn't know if that is a hardware or software issue.

     

    Another thing I have noticed is that when I have the FW and USB wires from the monitor harness plugged into my computer I can't even get the LED to flash when I touch the power button.

  • 290. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    I don't think the software on the Mac can make the power supply run differently (aside from the 'sense line' that has been discussed in this thread), so any issue would be hardware related.

     

    It is still a good idea to rule out your current installed OS. Just boot from an install disk & see what the display does. Original grey OS disks have Apple Hardware Test that can check the graphics card etc run that if you can see it.

     

    I suspect the backlight & the panel draws the majority of current compared to just the ports & the power light. It would explain why the PSU doesn't get hot, there may be very little load on it (just a guess). I'll try to remeber to check mine before I wake it in the morning :^)

     

    Have you actually got two power supplies? If the PSU works on another monitor I can't see how it would be the supply, unless they are not for the same model. Compare thier ratings.

     

    Are you near an Apple Store? You could try pleading with an Apple Genuis to allow you to try a 150W power supply if they have one available.

  • 291. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    pelachile Level 1 Level 1 (0 points)

    I don't have another power supply but both of the monitors are the same model (A1082) and I am using the power supply that came with my original monitor. Unfortunately I am way down in south texas and even though my city is fairly large (300,000) we don't have an apple store. The best we have is a Best Buy with a token apple section and some employees that know less about apple products than I do. I am going to try to boot from my snow leopard install disk like you said and see if that does anything.

     

    So do you think it might be a bad inverter? And is that hard to fix?

  • 292. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    dportis47 Level 1 Level 1 (5 points)

    Have you tried the paper trick?

  • 293. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    pelachile wrote:

     

    So do you think it might be a bad inverter? And is that hard to fix?

     

    I don't know what it could be, I was just pointing out that if the major electronics inside the monitor are not working then the power supply may not warm up.

     

    The test for a bad inverter board is the 'torch test' since the panel would be working without the backlight. The screen is so dark that you need to use a torch ffom the front to see anything. If you want to fix this yourself start googling for 'Apple Cinema HD Display 23 inch DVI' and the words 's ervic e  s ourc e'. I can't say much about it here because the mods are a little ban happy. You are looking for about 10MB of PDF.

     

    See my blog for more info if you really want to see how I fixed one.

    http://pixelchimp.net/blog/pixel-chimp/apple-23-cinema-display-possible-fix-shor t-long-short-error

  • 294. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    pelachile Level 1 Level 1 (0 points)

    I was getting ready to try and boot from my snow leopard install disk and it occured to me how would I know what is going on if I have the non working monitor hooked up?

  • 295. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    pelachile wrote:

     

    I was getting ready to try and boot from my snow leopard install disk and it occured to me how would I know what is going on if I have the non working monitor hooked up?

     

    Try it with the working monitor first to get an idea of how long to hold the C key down at startup. You should get the grey Apple screen after a short while then it will eventually go to the install screen.

     

    It's best to remove as many peripherals as possible to be sure that they are not part of the issue, so just hook up the keyboard & mouse.

  • 296. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    carolyn_21617 Level 1 Level 1 (0 points)

    My plug that goes from the monitor to the block also showed signs of melting. This happened to mine about 17 months after I started using the paper solution.

     

    The power block was getting extremely hot, so I was unplugging it in the evenings. Plugged it in this morning and the monitor is completely dead. Power block doesn't even heat up when plugged in, so that is obviously toast, and the plug and pins looks a bit singed. My apple tech asked if I wanted to try a new brick, but I'm giving up on this monitor. Not sure I can get an 150 watt to try anyhow. I'm going to spend the money on a new monitor rather than fedex charges of shipping and returning.

     

    Be careful, the paper solution may in fact cause a fire hazard.

     

    This is the only Apple product I've been disappointed with, even my original clamshell ibook still works.

  • 297. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    fyuan Level 1 Level 1 (0 points)

    Thanks, sir.

  • 298. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Drew Reece (Re:co) Level 2 Level 2 (310 points)

    I have written a small post from info that I was sent, it documents using a 120W LED power supply to run a 23" Apple Cinema Display. If you have enough technical skill it may be possible to replace the power supply for about $20-$30.

    http://pixelchimp.net/blog/pixel-chimp/replacement-power-supply-apple-cinema-dis play

     

    I can't add much to this info, but it may be useful for someone following along and wanting to try a cheap(er) power supply.

     

    As Carolyn noted above, the 'paper hack' can cause burning or short-circuit issues at the connector and isn't a good idea for long term use. Others have noted this in this thread.

     

    Eroni adds some info about the how the backlight (CCFL's) can cause the power supply to be overloaded.

  • 299. Re: Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code
    Richard Walker Level 1 Level 1 (40 points)

    I just encountered the same "short-long-short" LED code problem after having my hardware was PAT Tested (in the UK). Got it working again using jakobeon's solution (used tape). This will keep me going until I get a new 150w power adapter.

     

    Great support on here! Thanks all.

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