When hooked up to an external display, the computer is still fully functioning. I can tell by looking at the computer's "Display" list that the LCD screen isn't recognized at all -- the only display listed is the external one. Furthermore, when I press F1 and F2, as you would to adjust the LCD brightness, no onscreen graphic appears. And finally, when I close my laptop, the computer doesn't go to sleep like it usually would -- it remains functioning with the external display.

All of which is to say, as far as my computer knows, the LCD display is completely nonexistent.

Does this seem like a problem with the display cable, the LCD screen itself, or some other element?

Thanks!

Matt

⟐ Commented January 12, 2025 at 21:03 MST

When I hook up to external display there is no lines, everything looks as it should. If I shut the computer down for the night, when I first start it again, the display is fine but within minutes the lines are back.

http://img827.imageshack.us/img827/6519/...

http://img713.imageshack.us/img713/7754/...

http://img255.imageshack.us/img255/359/i...

From what I've read online, because the problem doesn't appear on external displays, it likely isn't the logic board.

I just opened it up and saw no apparent damage to the display cable connection to the logic board. I took apart the display and removed the display cable and could see no physical damage to that, either. The cable is wrapped in tape, however.

Is it possible that it's a bad display cable and only that needs to be replaced?

I did drop the computer about a year ago but haven't had any problems until this started a few weeks ago.

⟐ Commented February 10, 2023 at 1:11 MST

Hey Ralph thanks for the idea... stripped the computer down again and checked the fram rib and double checked the screws as you suggested... got all the right one in the right place and not ripped down tight, didn't see any dents in the lower case to show the screws touching. Same issue persists.

Can't see it moving in a pic, but that green light is with a battery with only 3 lights. Thanks again.

⟐ Answer accepted November 08, 2013 at 18:59 MST

I have left the "unspaced" words so that you can have a feeling about theproblem.

Thanks for your help,

Josue

⟐ Commented February 08, 2021 at 5:06 MST

⟐ Answer edited December 17, 2018 at 9:03 MST

When replacing the inverter board everything else broke. I'm not sure if I accidentally destroyed it with an electro-static discharge or if it was just poor timing. At this point I gave up and bought a new MacBook Pro. Putting the failed one aside for another time.

It has been over a year and I decided to have another try at fixing it since logic boards are now on eBay for around $250. Because it would not charge the battery I started by buying a new left I/O board, when that didn't fix the problem I ordered a new logic board.

I installed both the new left I/O board and the new logic board but I am still having trouble. when I press the power button:

• If the laptop is running on battery then, I hear the Hard drive begin to spin up, make a horrible clicking sound and repeat. The fans make a small jerking motion but do not spin up, the screen stays black and I DO NOT hear the start-up beep.
• If the power cord is plugged in, the hard drive spins up and stays spinning WITHOUT making the clicking sound that is heard on battery. But nothing else improves, the screen does not turn on, the fans make a jerking motion but do not start spinning, and there is no start up beep.
• If the power cord is removed the hard drive continues to spin normally.
• The new I/O Board does charge the battery.

Connecting a DVI cord has no effect (ruling out a bad screen?).

My question is: How do I know if my problem is related to a bad logic board or a bad left I/O board? Is there any way I can test each piece to prove which one is defective?

Derek

⟐ Answer edited November 25, 2012 at 8:50 MST

⟐ Answered March 09, 2014 at 14:36 MST

thanks for the answer.

Ben

⟐ Answer accepted January 17, 2010 at 16:48 MST

⟐ Answered March 06, 2021 at 21:18 MST

⟐ Commented October 17, 2017 at 1:33 MST

I have a macbook pro that I bought as "parts" and it booted up, but only to external HDD. Upon inspection (checked HDD, HDD flex cable, connection sites, etc), I discovered the entire board was covered in what I'm going to guess is coffee or coke. I'd like to soak the board because simple brushing is not getting it clean... Thoughts?

⟐ Commented September 22, 2017 at 19:05 MST

⟐ Answer accepted November 01, 2024 at 6:40 MST

For a shameful reason I teared down my computer, cleaned it with destiled water from coffee and now i see that some of the yellow tape, which i guess protected important electronical parts, isn't sticky enough any more.

for example that one that holds the keyboard-&-trackpad-connector on its place.

my question: can i replace it with normal office tape or does it have to be especially heat resistant?

thanks!!!

Jakob

ps: did you know that apple technicians work amazingly imprecise? i saw some scary scratches and broken parts inside that can only be caused by quick and rough working.

I know, i am the one who poured coffee over it, but still my discovery shoked me.

⟐ Commented July 17, 2019 at 22:52 MST

Before that, I had to underclock it from 2 to 1GHz to keep it stable (using Coolbook). The temperature at rest was around 55°C, and at full CPU load, it would reach 72 °C. The fan never kicked in at that temperature (never loud, but I didn't measure the speed at that point), but if it stayed that high for too long, the machine would freeze.

After the paste job, at 1GHz, even under load , the CPU temperatures (Core1, Core2 and CPU temperature diode) don't exceed 53°C. However, in these conditions, the fan runs at 3800 RPM (louder than what I remember it was before).

If I increase the clock speed, the fans accelerate, and reach 6000 RPM under load at 1.5 GHz. The temperature is then around 65-70°C

I measure the temperatures using Marcel Bresink's Temperature Monitor and the fan speeds with Lobotomo Fan Control. The latter is supposed to enable tweaking the fan speed settings, but it doesn't work here.

I also noticed that the temperature is now more volatile than it used to be.

Thanks in advance for your help.

⟐ Answered August 11, 2018 at 16:49 MST

With hdmi, dvi, vga (possible Dislpay port, thunderbolt)

I know for iMac you get the model number and find a controller board for it with the model number

⟐ Commented June 01, 2022 at 13:18 MST

Thanks!

⟐ Edited April 23, 2013 at 12:37 MST

I dis assembled and swapped the lower aluminum enclosure on my a1150 MacBook Pro. I followed the instructions meticulously and now upon reassembly the computer will not turn on.

the battery takes a charge and displays full, i have tried with and without power adapter.

When I press the power button, the two fans attempt to spin and appear to twitch. Then nothing, I have tried removing the hard drive with the same results.

Please help!

Thanks,

ANDY

⟐ Answered August 05, 2010 at 9:35 MST

Any idea what may be going on? Or if this is salvageable?

PS) this is a hardware problem, not a software issue.

⟐ Answered November 03, 2022 at 8:34 MST

OK, it took me six days to find an external monitor. I had tried on my flat-panel TV, but received error, "invalid format." Now, on an old flat-panel Dell monitor, two part answer, but bottom line is, external screen SEEMS TO WORK. However, in Mac mode, comes up obviously in wrong video mode and no way (none apparent to me) to adjust that. In Windows mode (Boot Camp), Windows XP comes up can read screen fine, then switches and error says "cannot read this mode" (paraphrase, forget the quote).

So, two questions now. 1) Must be my problem is NOT the logic board, so is it more likely the Mac laptop screen, or that "converter" card? 2) Maybe I just use an external monitor, but how do I change video modes when can't get it to come all the way up to place where can change? Thanks for advice.

⟐ Comment deleted November 14, 2016 at 10:03 MST

Am I running a CCFL or LED screen?

⟐ Answer accepted June 14, 2014 at 0:02 MST