Screen is dead

[SimonDodd]

I have a G4 powerbook, and the screen seems to be dead. That includes not only the display itself, but also the apple logo on the exterior and the little blinking light on the hinge. The laptop audibly boots, so it's not as though the laptop itself is dead; I had thought maybe there was a bad connector so I opened the patient up and everything looked good as far as a cursory visual inspection went.

Any ideas on how to diagnose and remedy this? What to look for, even? I'm reluctant to take it in for service when that's likely to cost as much as I paid for the unit in the first place.

 

[Eidorian]

Sounds like the backlights are out. An external display would work in the mean time but I don't recommend getting it fixed.

 

[SimonDodd]

If that's right - that it's the backlight - is that essentially the "ask not for which laptop the bell tolls" moment? Is replacing the backlight impossible for a user or prohibitively expensive either for me or for a service guy?

Interestingly enough, I just now plugged it into a TV - which I've done before - and I get "no signal."

 

[ElectroGhandi]

If that's right - that it's the backlight - is that essentially the "ask not for which laptop the bell tolls" moment? Is replacing the backlight impossible for a user or prohibitively expensive either for me or for a service guy?

Interestingly enough, I just now plugged it into a TV - which I've done before - and I get "no signal."

Logic board is broken.

 

[emt1]

If that's right - that it's the backlight - is that essentially the "ask not for which laptop the bell tolls" moment? Is replacing the backlight impossible for a user or prohibitively expensive either for me or for a service guy?

Interestingly enough, I just now plugged it into a TV - which I've done before - and I get "no signal."

Sell it to ifixit.com

 

[Dmac77]

Logic board is broken.

It's very implosible that the logic board is broken. Seriously, what makes you think that it's that the logic board, and not the backlight?

@OP-

It sounds like the backlight is dead. It's hard to replace them, and it won't be cheap to get it replaced by Apple. I would just use the PB with an external monitor, until you can get a new notebook.

Don

 

[ebika]

It may be the video card (requiring a logic board replacement) or the backlight. If the backlight is out, you'll still be able to see the display is you look close enough (use a flashlight on the screen to see if you can make out the pixels showing anything). If the display has absolutely no picture (minus backlighting of course), a board inside may be flaking or dead.

The graphics card on my mbp fried and it had the exact symptoms as the OP. Machine powered up, no display, no external display. Applecare replaced the logic board.

 

[sine-nomine]

Another possibility is that you need to replace the inverter cable and reed switch. The G3 iBooks were especially prone to having them fail, but I have heard other posters with G4 iBooks having the same problem. If that's all it is, a $25 part will get you back up and running, provided you are willing to spend a few hours making the repair.

If the cable is your problem, you will probably notice that the backlight will come on or flicker when the lid is open to shallow angles. Try barely opening the lid and messing with it for a while to see if you can get even a flicker out of it. Even if you don't, the cable could still be your problem.

Also, try shining a flashlight through the Apple logo and tell us if you can see an image on the screen. If you can, that points at the inverter cable or backlight issue, while if you can't, it could be the data cable to the screen or something more serious.

 

[ElectroGhandi]

It's very implosible that the logic board is broken. Seriously, what makes you think that it's that the logic board, and not the backlight?

@OP-

It sounds like the backlight is dead. It's hard to replace them, and it won't be cheap to get it replaced by Apple. I would just use the PB with an external monitor, until you can get a new notebook.

Don

Because he said he hooked it up to a TV and got no signal. He would have gotten display if it was just the backlight. READ.

 

[Dmac77]

Because he said he hooked it up to a TV and got no signal. He would have gotten display if it was just the backlight. READ.

My iBook won't display on my TV, but it works fine otherwise. I still don;t think that it's the logic board, especially sense the OP says that the PB chimes when he turns it on.

No it could be the graphics card, which would require a logic board replacement, but even if that is the case, the logic board isn't dead.

Why don't you read before you post.

Don

 

[ElectroGhandi]

My iBook won't display on my TV, but it works fine otherwise. I still don;t think that it's the logic board, especially sense the OP says that the PB chimes when he turns it on.

No it could be the graphics card, which would require a logic board replacement, but even if that is the case, the logic board isn't dead.

Why don't you read before you post.

Don

I would consider the graphics card, which is soldered to the logic board, to be part of the logic board. Therefore, the logic board is dead if the graphics card is dead, which it sounds like it is.

 

[Dmac77]

I would consider the graphics card, which is soldered to the logic board, to be part of the logic board. Therefore, the logic board is dead if the graphics card is dead, which it sounds like it is.

Th logic board as a whole isn't dead if the PB boots up.

Don

 

[SimonDodd]

Because he said he hooked it up to a TV and got no signal. He would have gotten display if it was just the backlight. READ.

Unless either the phono cable or the widget that connects the phono cable to the vid out is bad.

Interestingly enough, though, after walking away from it in frustration last night, I went back to unplug it from the TV this morning, and on doing so, the screen and apple immediately lit up! Astonished, I tried to get video, and when nothing came up (just a blank white screen), rebooted, whereupon the screen and apple were once again dark. That does seem to cut against the backlight gone bad theory.

 

[sn00pie]

It's not the logic board for sure. Sounds like a bad connector somewhere in the computer.

 

[SimonDodd]

Even more astonishing, I just went to turn it on just now to meet sine-nomine's request upthread to shine a flashlight through the apple, and - for the first time in two months - the fricking thing is working! Booted up, apple is lit up, blinker is lit up, screen is lit up.

So what the hell is going on? Are any of the issues mentioned above imaginable in an intermittent sense - the logic board flakes in and out, for example, or the backlight sometimes works and sometimes doesn't?

It's great that it's working - I can quickly back up my data - but I'm of course deeply interested to know what was - or, worse yet, IS - wrong so that I can have some sense of whether it'll flake out again.

 

[SimonDodd]

Realtime from my last comment, I'd barely hit reply when, all of a sudden, the screen started to show a whole bunch of interference and distortion before going completely white.

 

[sine-nomine]

Well, with that info, it probably is something to do with the GPU.

G3 iBooks had a tendency for the GPU to work loose from the logic board, and the symptoms were very similar to what you are experiencing. Many people who suffered this issue found that pressing the case right above or below the GPU could get it running again. In fact, when mine failed last year, I was able to get it working long enough to move off some important files by pressing very firmly just to the left of the trackpad. It didn't work for long, and I found that I needed to press both from the top and the bottom...something like the picture in the link http://www.blogcdn.com/www.engadget.com/media/2007/05/ibook1_small.jpg

Given that you have a PowerBook, you may be having a completely different issue, but try pressing on the case in roughly the same place indicated in the picture and see if it helps. If it does, you may be able to take the PowerBook apart and place a shim between the case and the GPU to keep pressure on it.