Level 1

2 points

Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code

Hello everyone.
This sounds like something of an epidemic... My Apple Cinema 23" HD Display (bought Dec. 2007) hasn't been turning on after a power outage hit our area last week.

The Computer and Display were OFF when the outage occurred. Everything was plugged into a surge suppressor. Everything ELSE plugged in to the suppressor is fine (including my Mac CPU)... but not the monitor.
It’s not dead-dead…. It’s a blank screen but there IS a morse-code flash on the LED (short-long-short). According to Apple Support’s LED Translation, it SHOULD be something to do with the power adaptor. The adaptor IS correct… a 90 watt… but just in case I bought ANOTHER 90w adaptor brick. I plugged the monitor to the new brick. THE RESULT WAS THE SAME.

I’ve tried power cycling, I’ve tried plugging it into different outlets, I’ve tried connecting to other computers. The same LED result remains.

And, yes, of course, I’ve got no Apple Support, and from what I read in similar posts, outside-the-warranty repairs could hit around $400. I REFUSE!

For now I have a Samsung monitor from Costco. It’s not bad, but it’s not the Apple monitor with its awesome color-fidelity.

I've read some other posts with the same problem (LED blink code and all) elsewhere but haven't got a solid answer.
I wonder… has anyone else incurring this same problem (with the same LED flashing deal) tried to use a 150-WATT adaptor brick? I would try this myself, but I’m currently financially unable (and personally unwilling) to throw more cash at this problem unless I know it’ll fix it.

Mac OS X (10.5.7)

Posted on Jul 18, 2009 7:03 PM

353 replies

Bertolt

Level 1

0 points

Apr 13, 2010 4:31 PM in response to matimac

Thanks, it worked! I can't believe I just shoved a sliver of a metrocard into a $1000 piece of hardware. Apple should recall these 23" monitors. I already had to shell out money for a new battery for my Macbook Pro. The technician said that it was definitely faulty and not worn out, but I had to buy another one because it was out of warranty.

Apr 19, 2010 5:20 PM in response to lebungleski

Great find. I just had the same problem as everyone else "short-long-short" after just moving my computer less than 5 feet. I was very careful in doing so. So I go to the apple store after ordering a new 90w, and no luck. For kicks we tried a 150w, and voila it works perfectly. The "genius" was going to order me a 150w, but at the last stage he said that he was unable to. It seems that because I didn't have a serial number for a 30" display you are unable to order a 150w power adapter. He left it up to me to find a serial number and that one from their floor would not work. I have been so frustrated not being able to get any help from apple support, they have never heard of this, and I have to find a serial number and solution myself. Makes me so angry. But finding this has given me a glimmer of hope. I did finally manage to get a serial number and ordered a 150w from the apple store, but I will hold off buying it if I can get the inverter trip to work with a piece of paper or something. You are the true "genius" for finding this cheap fix. Thanks to all for contributing to this thread.

tgibbs

Level 1

70 points

Apr 27, 2010 1:49 PM in response to drrock200

Another success for the block-the-middle-pin solution. Problem was similar to what others have described. I needed to move my system temporarily, so I shut down my system and carefully unplugged my monitor and moved it to another room while some work was being done in my office. When I moved it back, I got blank screen with the short-long-short code. As it happens, I have two of these, so I was quickly able to verify that the brick was fine. Blocked the middle pin with a strip of paper and it came up fine.

samko

Level 1

11 points

Apr 28, 2010 4:55 AM in response to tgibbs

I just moved my Cinema Display from one desk to another and when I plugged it in again I got the blinking LED code. Having read the previous posts, it seems either moving the display would cause such a problem or it's a problem with the power supply. I guess most users, like me, have their display (power adaptor) plugged in since day one and any problem with the power adaptor won't show up until the next power cycle. I am going to try the "covering the middle pin" solution tomorrow and have my fingers crossed.

samko

Level 1

11 points

Apr 28, 2010 8:30 PM in response to samko

The solution really works! If the middle wire is indeed a ground and the display detects a voltage there (as it shouldn't) and won't turn on the display to protect itself from damage, then there must be a grounding fault in the power supply. Since the solution works with at least the majority of the users here, Apple should take a look at the design or material used in the power supply. Like I said before, the power supply might become faulty after a couple days of initial use but most users won't find out until the next power cycle (either through unplugging the power supply or a black out)

I bought my 20" display in 2007 and I don't think I have ever unplugged the power supply until yesterday.

BTW, thanks a million to Jakobeon.

Message was edited by: samko

tgibbs

Level 1

70 points

Apr 28, 2010 10:23 PM in response to samko

It seems pretty clear that the problem is not with the power supply "brick." I have two identical monitors. When one started giving a blank screen with the short-long-short code (after turning them both off for a few days, then trying to bring them back up), the first thing I tried was switching the bricks. The working monitor worked with either brick. The non-working monitor would not work with either brick. Blocking the pin fixed the problem.

samko

Level 1

11 points

Apr 29, 2010 5:18 AM in response to Michael Pitogo

You are right. I forgot you mentioned you had two "bricks". So by blocking the middle pin creates a "floating" ground inside the display. Something inside the display is 'short circuiting' to the ground? The middle pin carries the ground from the display to the electric outlet ground. So the trick would still work if we just block the ground of the wall plug and not covering the middle pin? I will try that tomorrow.

tgibbs

Level 1

70 points

Apr 29, 2010 7:25 AM in response to samko

The other curious observation is that a number of people have found that affected monitors work properly if they use a 150 watt brick instead of the 90W brick that is standard for this monitor. This suggests that the failure is in the monitor's circuitry that checks for the correct power supply. So maybe blocking the pin "fools" the damaged circuit.

tgibbs

Level 1

70 points

Apr 29, 2010 7:38 AM in response to tgibbs

It seems likely that the monitor performs a check for the correct wattage brick only at startup, since the brick cannot be changed without a powerdown. This would explain why so many people have reported that the monitor was working fine before they powered it down, and then refused to come back up when power was reapplied. Very likely, the power-check circuitry failed sometime before, but it didn't matter as long as the montior was running.

samko

Level 1

11 points

Apr 29, 2010 11:02 PM in response to tgibbs

With the "block the middle pin" in place, and the display running fine, I unplugged the wall socket and taped over the ground. When I connected the wall plug, the display again failed to work and gave me the LED code. Then I took the mini plug out and re-block the middle pin with a thin piece of paper. The fix worked again, as expected. I doubt the middle was just the ground pin. It must also be doing something else. Anyway, I am just happy my display is working now.

tgibbs

Level 1

70 points

Apr 30, 2010 8:04 AM in response to samko

The third pin on the wall plug is not the only ground. I don't know of any device that requries this pin to be connected to operate. It is a safety feature, intended to protect the user against shorts. One of the other two pins (the wide one, if correctly wired) is a "neutral" pin that is a kind of ground, although it is not guaranteed to be at true ground potential. If you blocked all ground, no current would flow, and the device would not operate.

May 4, 2010 9:08 AM in response to tgibbs

Another success with the piece of paper method. I am ordering the 150 watt adapter just in case. The paper method is a little tricky, but with enough tinkering I was able to block the middle pin. Thanks to jakobeon.

tgibbs

Level 1

70 points

May 10, 2010 8:31 AM in response to wxperson

It took me a while to figure out also. I don't have a picture, but perhaps some additional description would help.

You are going to cut a thin strip of paper around 1-2 mm wide and maybe 3-4 cm long. fold it in half. Poke it down into the center of the plug (on the cable from the monitor) as far is it will go. The idea is to block only the middle contacts. Take the "excess" that sticks out and fold it down around the outside of the plug (this creates the "W" that people speak of; the middle of the W is the part that pokes down into the plug, and the sides are the parts that you've folded down around the outside of the plug). You will hold the ends of the strip that you've folded down around the outside to keep it in position as you plug it into the power brick. It took me about three tries to get it right.

May 13, 2010 7:57 AM in response to matimac

I was desperate to find a solution after a power outage caused my monitor to go black. This discussion SAVED me, especially the youTube video that explains it all. I was trying this fix but I was using the wrong plug. I thought at first it was the BIG 3-pronged plug that goes into the power adapter--but it was the other small one. It worked on the first try after I watched the video. Thanks EVERYONE!

May 17, 2010 6:20 PM in response to lebungleski

WOW! Whoever thought of that idea to block the middle pin is a genius. How did you arrive to that solution? What exactly is being defeated when you do that?

The electric company came last morning to shut the power off for 20 seconds because they were "working on the meters." I turned off all my computer equipment, although I didn't bother shutting off the powerstrip and the ACD shuts off anyway. When the power came back on, everything worked as normal. Except the Apple Cinema Display! I too thought it was fried until I noticed the short-long-short LED blinking and went to look it up. I found this discussion thread and tried blocking the middle pin with two extremely thin slices of electrical tape. Worked like a charm! However, I'd like to know what exactly this is doing and why it works.

Anyway, saved me from spending $400 for apple to fix it! Amazing! Once again thank you to whomever thought of this.

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Apple Cinema Display 23" - Blank Screen, "short-long-short" LED code