Backlight turning off, inverter-board changed

Question

iMac Intel 27" EMC 2309 & 2374

iMac Intel 27" EMC 2309 (Late 2009, Core 2 Duo 3.06 or 3.33 GHz) ID iMac10,1, EMC 2374 (Late 2009, Core i5 2.66 GHz or Core i7 2.8 GHz) ID iMac11,1

467 个问题查看全部

Joe @joe82638

声誉积分: 73

4

2

发帖于: 2012年10月19日

更多选项

Backlight turning off, inverter-board changed

Hi, my late 2009 iMac 27" is killing me. Display goes black 10 times a day. When I hold a flashlight to the screen I can see stuff on the screen. External Monitor works fine. Regarding to some other articles on ifixit, the backlightboard should be damaged.

So i ordered one from the US (I´m in germany) and replaced the old one... same failure *crying loud*.

Do you think i should change the backlight cable also? I can only find one on the internet and thats &##* expensive (more expensive then the board itself). Where do you guys get those cables?

Does anyone know why the display is turning off in such irregular intervals? Is it a heatproblem??

Maybe i should plug out the display-thermal-sensor-cable an see if it is still turning off?!

Thank you!

已回答！ 显示答案我也有这个问题

这是一个好问题吗？

是否

得分 6

19条评论

Start by resetting the SMC - http://support.apple.com/kb/HT3964 See if that sets things right. Without knowing which model you have we can't answer this - Please give us the last four digits of your serial number so we can correctly identify your system.

由 Dan 完成的 2012年10月19日

thx Dan, already resetted the SMC multiple times. My Serial ends with 55PJ.

Greetz Joe

由 Joe 完成的 2012年10月20日

iMac "Core i5" 2.66 27"

Model No: A1312 (EMC 2374)

由 Dan 完成的 2012年10月21日

Just to make sure were on the right track here. Your system has LED backlighting not CFL's. So to be clear here you replaced the display LED backlight unit 'backlighting board' as well as the LED driver board 'inverter changed' correct?

由 Dan 完成的 2012年10月21日

I only changed the LED-Driver-Board by following this guide: iMac Intel 27" EMC 2309 and 2374 LED Driver Board Replacement

由 Joe 完成的 2012年10月21日

显示更多的14条评论

添加一条评论

4个答案

已选择的解决方案

Dan @danj

声誉积分: 482千

Self employed contract worker

35

332

971

发帖于: 2012年10月22日

更多选项

Check your display settings. Turn off the Ambient Light setting. Also check your Desktop & Screen Saver settings make sure the Start Screen Saver is put to never. Restart your system and see what happens.

这个答案有帮助吗？

是否

得分 1

6条评论:

so theres a second board i could change? I cant find anything on google on "backlighting board imac". Is it part ot the Display or maybe the board next to the driver board? thx

由 Joe 完成的 2012年10月23日

ah .. didnt see your last comment. Screensaver is disabled. There´s no "Ambient Light" setting in the Displays preferences availible. I know the option to automatically adjust brightness from my macbook but the iMac doesnt have this feature( or the killd it in the Upgrade to MountainLion).

由 Joe 完成的 2012年10月23日

Just want to make sure were not looking for snipes. Not all of the iMacs have an Ambient Light sensor so the option may not show up. Yes there is a second part here that could be the issue but I don't think it's the case here given the symptoms. The LED backlight panel which is part of the display unit. I still think something else is the cause here. The LED panel rarely fails and when it does its only an LED or two that die (depending on your system and display you have12 - 18 LED's along the edge).

由 Dan 完成的 2012年10月23日

what do you think about the backlight cable? Could this be the reason for my problem? Hard to find one over here...

由 Joe 完成的 2012年10月23日

No, I don't think its the cable. I'm starting to think its something on the logic board. Can you run Apple Hardware Test http://support.apple.com/kb/HT1509 to see what it tells us.

由 Dan 完成的 2012年10月23日

显示更多的1条评论

添加一条评论

Start by resetting the SMC - http://support.apple.com/kb/HT3964 See if that sets things right. Without knowing which model you have we can't answer this - Please give us the last four digits of your serial number so we can correctly identify your system. — Dan
thx Dan, already resetted the SMC multiple times. My Serial ends with 55PJ.

Greetz Joe — Joe
Just to make sure were on the right track here. Your system has LED backlighting not CFL's. So to be clear here you replaced the display LED backlight unit 'backlighting board' as well as the LED driver board 'inverter changed' correct? — Dan
I only changed the LED-Driver-Board by following this guide: iMac Intel 27" EMC 2309 and 2374 LED Driver Board Replacement — Joe
so theres a second board i could change? I cant find anything on google on "backlighting board imac". Is it part ot the Display or maybe the board next to the driver board? thx — Joe
ah .. didnt see your last comment. Screensaver is disabled. There´s no "Ambient Light" setting in the Displays preferences availible. I know the option to automatically adjust brightness from my macbook but the iMac doesnt have this feature( or the killd it in the Upgrade to MountainLion). — Joe
Just want to make sure were not looking for snipes. Not all of the iMacs have an Ambient Light sensor so the option may not show up. Yes there is a second part here that could be the issue but I don't think it's the case here given the symptoms. The LED backlight panel which is part of the display unit. I still think something else is the cause here. The LED panel rarely fails and when it does its only an LED or two that die (depending on your system and display you have12 - 18 LED's along the edge). — Dan
what do you think about the backlight cable? Could this be the reason for my problem? Hard to find one over here... — Joe
No, I don't think its the cable. I'm starting to think its something on the logic board. Can you run Apple Hardware Test http://support.apple.com/kb/HT1509 to see what it tells us. — Dan

donmoron @donmoron 声誉积分: 91 3 1 · Answer 1 · 2012-11-25T13:24:30-07:00

donmoron @donmoron

声誉积分: 91

3

1

发帖于: 2012年11月25日

更多选项

looks like the GPU, i had similar problem - check here: http://forums.macrumors.com/showthread.p...

这个答案有帮助吗？

是否

得分 1

6条评论:

Hey Don,

thx for the link. This sounds interesting. I think i lack the skill to find that "enabeling" - pin and put voltage on it without killing some other parts. My Mac works most of the time. The display isnt´t permanently black as yours. I noticed that it fails more often in shorter periods the higher the brightness setting is. I was looking for a new logic board but the prices are way to high to be economic.

Maybe ill come back to your method once the display fails permanently :)

THx Don...

由 Joe 完成的 2012年11月26日

Just in case, I would recommend you keep a good backup of your data and make sure you keep it updated.

由 Dan 完成的 2012年11月27日

yes, im running a TimeMachine. I did a clean install algain to see if its software related. This Problem is solo annoying. Mostly the Display fails when i got the most work to do :)

由 Joe 完成的 2012年11月28日

It might be a faulty vertical sync cable, they say: iMac 27" Black Screen

It´s cheap if you find a used one.

由 Yrjo Pesonen 完成的 2013年1月31日

I did some work on my iMac 27" at home and the thin ribbon cable to the lcd board stripped off the gold, I was trying to be careful but the connector did the damage when I was unplugging it, I ordered a new ribbon cable, but the fix I found was to use some supper glue on the ribbon and then press the gold connectors quickly with out gluing it to my fingers, that worked well and I have the new one as a spare. I think Apple could use stronger connectors and still be a great machine even when folks do their own work, It hurts Apple to make it harder for folks to work on their machines. In the long run more folks would use iMacs if repairs were cheaper and easier. Most jobs are difficult because of the feeble connectors, one wrong move and they can break and turn a simple replacement job into a nightmare job in a split second. I think Apple has done this on purpose. IMO

由 Kurt L Nelson 完成的 2017年3月27日

显示更多的1条评论

添加一条评论

Georg Kipp @schosch 声誉积分: 13 1 · Answer 2 · 2019-11-09T17:55:50-07:00

Georg Kipp @schosch

声誉积分: 13

1

发帖于: 2019年11月9日

更多选项

I had the same problem with a 27-inch iMac 2009 i7, I changed the inverter board several times without success. Then removed the flat cable between inverter board and display, which I had previously renewed and curiously, the backlight is now permanently on.

Although the temperature sensor cable of the LCD was also defective, but had the consequence that the backlight did not even concern. The temperature sensor is a standard component, a 2N3904 transistor and easy to replace.

这个答案有帮助吗？

是否

得分 1

1条评论:

Yep same thing, remove the cable between inverter board and display from the inverter end and display stays on and working, using MacFan control and everything ok

由 Pao De Queijo 完成的 2020年7月15日

添加一条评论

Transistor Girl @transistorgirl 声誉积分: 53 3 1 · Answer 3 · 2022-04-20T04:26:27-07:00

Transistor Girl @transistorgirl

声誉积分: 53

3

1

发帖于: 2022年4月20日

更多选项

You guys mean the vsync cable right? I just ran into the same issue on a mid 2011 27". Inverter board was faulty, so i've changed it, now if i turn the brightness control over 5, it starts to black out. The only way to wake it is the ctrl+shift+eject then a mouse click, but then it does it again.

I have to mention though, that the broken inverter board is the Sumida 612-0094 and i could only replace it with the V267-604HF...dunno if that could be a problem, because it's used inside the same iMac with probably the same LCD display...

If the problem can be the board, please tell me, I can return it today or in a few days if it's not ok!

这个答案有帮助吗？

是否

得分 0

添加一条评论

iMac Intel 27" EMC 2309 & 2374

Backlight turning off, inverter-board changed

4个答案

添加你的答案