3 Replies Latest reply: Mar 29, 2015 10:39 PM by Jennifer Street
Jarveye Level 1 (5 points)



Ii have two 23" cinema HD displays on the mac listed below. they have worked fine for ages, but today i turned on and one of the displays did not come on, instead the power light flashed periodically with a long pause then a short flash, long flash and short flash.


i have searched for solutions and i found this article for LCD displays:



which stated that this kind of flash means the power adapter isnt working, but i tried swapping the adapted/power cord with the other display without luck.


this other article:



which states it may be the backlight, but i wanted to try here to see if there was any other potential solutions, if not whats my best bet with getting it resolved?



things ive tried:

i tryed the problem display on it's own to make sure it wasnt a problem with having dual screens, it still didnt work.


I tryed swapping the power adapter, the adapter seemed to work fine with the working monitor, and the other one didnt help with the faulty display.


I tryed both display sockets in the back of the mac to make sure the connection to the mac wasnt the problem.


i thought the cable which runs to the display to the power adapter may be worth trying to swap, but while i thought this was removable i couldnt seem to disconnect it from the back of the display and didnt want to pull too hard incase i broke it is it fixed?

Mac Pro 2x2Ghz Dual Core Xeon, Mac OS X (10.4.11), 6CB 667Mhz DDR2 FB DIMM
  • Jarveye Level 1 (5 points)



    if theres no easy fix i need to know, i live in the shetland isels and getting to a apple tecnician is a bit of a problem... will probably need to ship it away...


    any advice much appreciated!

  • elfstr0m Level 1 (0 points)

    I had the same issue and appreciate your links, thanks. However the indication (short-long-short) was not accurate. I switched adapter with no luck, but when I switched to another 23" Cinema Display it worked fine as in your experience.


    There has to bee something else wrong with our monitors. I was lucky, we had two others standing around so I'm all set.


    I have no other information that might help you, sorry.

  • Jennifer Street Level 1 (5 points)

    Does anyone have any troubleshooting tips for this issue? My McBook Pro hard drive went down so i was without my computer for a couple of weeks. I just got a new one installed, got it all set up from my backup and now my display isn't working. I checked the display set up it is seeing the display but nothing is showing up on the screen. Any help is appreciated!