ibook g4 lcd problem

Hi jw and welcome to Apple discussions,

I also hooked it up to an external monitor via mini-vga to vga adapter and the external monitor just seems to ask like its in sleep mode.

Sleep mode? Like not reacting to keyboard commands or running screen saver?

I was able to get the monitor a come on a few times. I got a flashing folder with a ? mark which I understand because I don't have the OS installed on the drive.

Right.

But soon after the screen would glitch then go dim

Dimming of the flashing folder and ? or no pic and "traveling ghosts"?

then eventually go black. I also try holding a bright light to the back of the screen to see if the the LED lights in the lcd

Only LEDS in the newer MacBooks. CCFLs in this model.

but I don't see any sign of it booting.

If you still have the flashing folder and ? it would only be visible through the Apple logo in the back center.

Could it be the inverter board or inverter cables? The hinge on the LCD broke in 2 place right where all the cables come up from the logic board into the lcd bezel.

Left or right?

Could one of these cable have been damaged and causing this problem?

Left cable - inverter cable and Airport antenna.
Right cable - LVDS cable and reed switch
Either could cause the symptoms you're seeing but in the case of the inverter cable you'd see the flashing folder in the middle.
If it is the inverter and it's a short vs an open you could blow a fuse on the logic board (it's tiny and black).
It could also be a GPU problem. These had a ATI Mobility Radeon 9200 4x AGP and I have seen those fail as well as the BGA problem. If this is the case it is possible to find a replacement chip and reball it onto the motherboard.
The broken hinges would have to be addressed.
Richard

jw,

-It would glitch with a couple horizontal lines in the middle of the screen

Unfortunately that sounds like the GPU chip. Especially the glitch w/ the lines.

then, it would go dim like it does when you don't touch the track pad for a minute during use. The only thing different is that when i touch the track pad it wouldn't brighten up like it normally would, then it would just go completely black.

This iBook had a ATI Mobility Radeon 9200 4x AGP graphics chip in it and they can fail and that's what this sounds like. Practically confirmed since the external monitor acts the same way.

-I was thinking of going ahead a replacing the inverter and the cables on both sides since it doesn't seem like it would be too expensive.

From what we know now that doesn't seem like it would help.

if it where the cables and inverter would I still be able to use an external monitor?

Yes.

I hooked it up to an external monitor but couldn't get any display.

Practically guarantees that it's the GPU chip. It could possibly be the BGA attachment also. Pressure on the GPU would confirm this.
RIchard

This is out of my region of knowledge; but:-

One knows the hinge region needs repair. Years ago, the G4 iBook had a known problem in which rotating the hinge rubbed the insulation of the wires in the LCD cable (I believe). Apple in Germany replaced the cable free. (German law.)

Was the notorious 'shim' addition by Apple near the GPU on the G4? The Danish government attributed the solder joint's failure to repeated heatings & coolings (cycling on & off). Because the iBook with MacOSX 10.2 first turned a tiny laptop into a graphical, Unix workstation (which makes it famous in my mind), I assumed the GPU was, technologically, unexplored territory: 2D & 3D OpenGL instructions were being passed off to it, for the first time in a PC, let alone a laptop. (Linux still hasn't caught up.)

My questions would be, can the problem be diagnosed definitively by the OP? Can he distinguish among, for example, the cable to the LCD, a solder joint on the logic board, or the GPU itself? The occasional flickering of an image suggests its not the GPU itself, but a loose connection.

The refusal of the VGA to mirror an image does strongly suggest the logic board. Where were the shims placed? Where (on the case) are the other weak solder joints? Could he press there?

Also, if he twists the monitor very slightly and sees an image for an instant, would that suggest a loose connection? (The LCD cable was soldered to the logic board wasn't it; and wasn't this a trouble spot?) Is the VGA wired so a failure of this connection could disable it as well (without damage)? Would pressing or twisting somewhere to create a flash of an image suggest his fuse is intact and he need focus on that component. In particular, if a tiny twist of the hinge causes the flash of an image, need he only replace the hinge components (which he must anyway)?

Because the OP would likely never bother an expert with these questions, I shall. They ask for actual diagnostic tests people could perform at home. (I'm not just praying for a miracle here, I hope). 🙂

The failure of VGA is the single 'doom & gloom' observation. I don't know how these machines are wired; but, for example, didn't they adjust the screen brightness according to an ambient light sensor? Doesn't software or firmware blank the screen after a while? I'm not sure what effect a bad cable, for example, might have on these circuits.

Bruce

Three things struck me a few moments ago (sorry). You said it made 'the right sounds' when booting, it showed a question mark, it acted as if it slowly went into sleep mode and wouldn't come out.

Beeps & flashes when booting

That may not be a hardware problem, because there should be (if I remember correctly) a diagnostic beep pattern if there is no keyboard, and most likely if there is no monitor on a laptop). Unfortunately, I can't find a list of these. Others can. When booting, listen for unusual beep patterns and patterns of flashing LEDs on the top edge of the cover (when closed). These can tell you what hardware is malfunctioning.

EPROMs

The PRAM controls the question mark (where's a bootable disk?) and the PMU chips control sleep mode. Each can be corrupted by a discharged PRAM battery or power fluctuations (vacuum cleaners running in the house).

I was under the impression that the G4 iBook had no battery, and the values were copied anew during each boot. However, this document suggests otherwise. Try removing your Li-ion battery and using the wall cord, just to be sure you're getting enough power. If doing this changes any of the things listed below as stored in PRAM, you may not have a battery.

Mac Family Batteries
http://support.apple.com/kb/HT2295

What is Stored in PRAM?
http://support.apple.com/kb/HT1242

Because the Power Mac has individual parts once can test, I just checked what Apple does when they have similar problems:

Power Mac G4: Screen is Black, Startup Tone Present, Drive Operates
http://docs.info.apple.com/article.html?artnum=95055

Power Mac G4: No Video
http://docs.info.apple.com/article.html?artnum=95043

Finally, I found this:

Troubleshooting Portables that Won't Turn On
http://support.apple.com/kb/TA25686

Sadly, it says nothing of bleeps & flashes.

Each of the above start by recopying the PRAM and PMU from ROM chips. However, you may wish to look for one of these symptoms first.

When should the SMC or PMU be reset?
http://support.apple.com/kb/HT1894

Resetting PRAM & VRAM
http://support.apple.com/kb/HT1379?viewlocale=en_US

Resetting PowerBook and iBook Power Management Unit (PMU)
http://support.apple.com/kb/HT1431?viewlocale=en_US

Sometimes pressing 'C' just doesn't boot the CD. (I think it wears out.) Try holding down 'Option' instead, for a list of bootable drives. Hold it down long enough. Did your computer come with something like this (that came with my G3 iBooks)?

Apple Hardware Tests on CD
http://docs.info.apple.com/article.html?artnum=112432

If not, there's the Apple 'Genius', or a LiveCD Linux. Even the Intel version of Linux that boots on Windows machines has some tests for PPC machines, and can test the partition table & file system on an HFS+ disk. The 'Apple Hardware Test' is the way to go, though.

If your drive has logs of its failed boot, Apple would have read them. I have lots of ways of reading them, if they forgot. Others will have more. Just write back.

Also, your hard disk has early partitions with basic device drivers, necessary to boot. Presumably a CD has these, and a scratch would be bad.

Look & listen for beeps & flashes. Nothing out of the ordinary means, I suspect, a firmware or software problem. Someone may know of a list. Good luck!

Bruce,

..the G4 iBook had a known problem in which rotating the hinge rubbed the insulation of the wires in the LCD cable (I believe). Apple in Germany replaced the cable free. (German law.)

Apple USA reinforced w/ spiral wrap in this area.

Was the notorious 'shim' addition by Apple near the GPU on the G4?

It's actually on the GPU itself, pressing on faulty BGAs.

The Danish government attributed the solder joint's failure to repeated heatings & coolings (cycling on & off)

The failure was in chip U28 which is a dual voltage regulator. The main failures were on pins 1 an 11 which were ground references. The problem seemed to me to be bad early formulas of lead free solder.

My questions would be, can the problem be diagnosed definitively by the OP? Can he distinguish among, for example, the cable to the LCD, a solder joint on the logic board, or the GPU itself? The occasional flickering of an image suggests its not the GPU itself, but a loose connection.

To me it was the way it flickered and "glitched" then slowly dimmed down. (an failure that I describe as "traveling ghosts". Dark shadows that move and are often rectangular are a symptom of a failed GPU chip.

The refusal of the VGA to mirror an image does strongly suggest the logic board.

Yes specifically the GPU but have heard that BGA failure could mirror this symptom.

Also, if he twists the monitor very slightly and sees an image for an instant, would that suggest a loose connection?

Yes.

(The LCD cable was soldered to the logic board wasn't it; and wasn't this a trouble spot?)

No both the inverter cable and the Low Voltage Display Signal cable attach w/ connectors to the logic board. The failures occur at the hinge point in 100% of the cases I've seen and yes in this case flexing would cause a flash. However in the case of the inverter cable it would be an open. A short to ground would take out the fuse on the logic board.

..didn't they adjust the screen brightness according to an ambient light sensor?

Maybe later MacBooks and certainly the ALS iMacs. (G5)
Richard

Here are some photos that Spudnuty might be able to use. Unless your iBook is under warranty, it doesn't matter much which part of the logic board is broken, unless you want to try a shim. (I followed the links and ended on the wrong side of the logic board.) You appear to have diagnosed the problem enough. 🙂

[iFixit Guides to the G4 iBook|http://www.ifixit.com/Guide/search/iBook+G4]

[Guide to Nightmarish Repair of your iBook|http://www.ifixit.com/Guide/Device/iBook G4_12%22_800_MHz-1.2GHz]

[Click on these photos and they'll enlarge.|http://www.ifixit.com/Guide/Repair/iBook-G4-12-Inch-800-MHz-1-2-GHz-Lo gic-Board/173/9]

Hey jw,
Here's a pic of the location of the GPU that I posted in my album at PhotoBucket:
http://s291.photobucket.com/albums/ll306/spudnuty/?action=view&current=Weirdgrap hics.jpg
It seems to me that I've mislabeled the LVDS cable or I don't recognize the model and size.
The 1.2 has a single continuous heat sink but the location of the GPU is similar.
The LVDS on the 1.2 is routed under the bottom in the 1.2 I'm pretty sure. Just before it makes a turn and plugs into it's socket is where the twin vreg is located. It's designation is U28 but problems w/ that chip will give you the Corey Arnold problem.
When you press down near the track pad you disturb the BGA contact of the GPU and the video will get wacky.
The chip is under that large heat sink so pressure from the top might be difficult or problematic.
OK just pulled a 1.2 12" logic board.
GPU is here marked ATI:
http://s291.photobucket.com/albums/ll306/spudnuty/?action=view&current=1212iBook LogicGPU.jpg
and a place to apply pressure from the bottom:
http://s291.photobucket.com/albums/ll306/spudnuty/?action=view&current=1212iBook underGPU.jpg
You'd have to take the bottom case and shield off.
Let me know what happens. I've given this advice on the GPU pressure before but never heard back on if it works. I suspect it would if only as a diagnostic.
You'd have to apply the pressure and boot w/o disturbing the pressure on the GPU.
Getting a good image would verify a reball is in order.
Richard

Message was edited by: spudnuty

Great photos!

Comparing the heat sink with that on my Quicksilver's graphics card (which has a huge fan), I can see why there could be a problem. So, about 2-3cm in from the USB ports is where the GPU sits (on the upper face of the card)? Squeezing there might find the break?

Is re-baking the board in an oven reliable? My preference is for the PPC chip with 128-bit AltVec support, but Apple is going Intel and a little more generic, by dropping its strong support of Firewire. The MacBooks, I understand, haven't these problems.

I've a little G3 iBook with a bad logic board, and I've little choice but to repair it myself (cough). However, my resources are high on labor and low on cash.

Evaluating one's software and software needs, which dictate hardware needs; and possibly trying a MacBook might be in order, not to throw good money after bad. Nevertheless, I believe one needs a 'hardware backup' (extra computer) when one goes bad.

I, too, should be curious to know what most people do about such problems as these. (If the board has gone this long without problems, it may warrant a repair.)

Bruce,

Comparing the heat sink with that on my Quicksilver's graphics card (which has a huge fan), I can see why there could be a problem.

Well Dale at Superior Reball says that chip doesn't put out a lot of heat. Which explains why I never hear the fan turn on except at startup.

So, about 2-3cm in from the USB ports is where the GPU sits (on the upper face of the card)? Squeezing there might find the break?

If you press from the top you'd have to push directly on the large heat sink so I didn't think that would be the best way.
In that photo of the bottom the large open area is where the chip is attached on top. So I'm saying press there maybe using a square plastic thing to spread the pressure and electrically insulate.
So about ball grid arrays, Google:
"ball grid array"
and peruse those three pics that show up.
Reheating, called reflowing professionally I think keeps the same defective solder on the contacts and the problem will reoccur. Dale at Superior agrees.
Richard

Message was edited by: spudnuty

{quote:title=spudnuty wrote:}
Well Dale at Superior Reball says that chip doesn't put out a lot of heat.
Which explains why I never hear the fan turn on except at startup.{quote}

Shim

Wow! My G3 iBook has a similar GPU, I think. The only sensor in my iBook I know of is on the hard drive. My fan never comes on and blasts through those pinholes either. These were the machines that had GPUs that understood OpenGL, and MacOSX 10.2 passed both 2D and 3D OpenGL graphics commands (rotating icons) to the GPU rather than CPU. That, and the G4 w/AltVec, is why I call them the first laptop, Unix workstations.

So I'm saying press there maybe using a square plastic thing to spread the
pressure and electrically insulate.

Sounds great. The insulation might keep the little solder balls closer to the termperature of the GPU. Computing was not my full-time profession; however, I think circuit board companies now compress the balls as they heat by spraying them with a glue-like substance.

J. White has successfully diagnosed his problem, found an inexpensive, experimental solution that can't harm his machine, and need only deal with the hinge.

Lubricating Metal Hinges

This isn't my expertise either (though it was my late father's). I'm assuming a titanium hinge wouldn't break, and it's and an aluminum or a steel alloy. Once the hinge is fixed, by replacement (during the teardown) or brazing, I've heard mention of using a molybdenum disulfide dry lubricant to prevent trauma.* People here no doubt have better information, but a dash of 'Z Moly-power' can likely be found from your local gun smith (if in the USA) or local machine shop.

Repairing Metal Hinges

With the case off, your local machine shop might be able to silver-solder and 'lap' the hinge as well. Should one want to start a new profession, try

Silver Solder for Aluminum
https://www.tinmantech.com/html/soldering.php

(J. White, I see you have a 'MacBook Pro'. Didn't notice, sorry. Everyone needs a backup computer. But, if you've decided to drop your iBook into the recycling bin, feel free to send e-mail this way. 🙂 You seem to have had a pretty good board to have lasted this long - I think SpudNuty's kludge, at least, worthwhile. Try and stick with the same board.

So, J. White, you have a diagnosis, and you have several possible solutions for both problems. Good luck!

Bruce

*This is my profession, geology. In the field, I can't tell molybdenite from graphite. Graphite, however, being slightly conductive of electricity, corrodes most metals, even aluminum. Molybdenite doesn't.

Thanks again to Spudnuty for the great photos.

Bruce,

The insulation might keep the little solder balls closer to the termperature of the GPU.

I say something insulating to prevent touching the board or damaging the SMT devices.

I think circuit board companies now compress the balls as they heat by spraying them with a glue-like substance.

My understanding is that the flux tacks them in place as they have a screen that positions them.

Lubricating Metal Hinges

I drive them apart and use .Moly Grease from the hobby shop for lubing

I'm assuming a titanium hinge wouldn't break

No the hinges don't break but the frame does or the rivets fail. I've tried to repair the frames but I think they're pot metal and I can't control the heat well enough to affect a repair.
Parts are easily purchased online.
I've also swapped displays from G3s.
Richard
Richard

Spudnuty,

spudnuty wrote:
I say something insulating to prevent touching the board or damaging the SMT devices.

You were clear. As you know, electrical and thermal insulation go together like peas and carrots.

I've tried to repair the frames but I think they're pot metal ... .

Aahhh! Let's hope SJ didn't hear anyone write that!

Great photos, especially the second one. Sorry if I appeared to prod you for knowledge, but I wanted to see how well one could unconventionally (but definitively) diagnose this problem, then offer those solutions users have taken, but Apple can't.

It's such a common problem, one should maintain a 'User Tip' and just forward patients there to follow an algorithm before returning. Does it hurt when I press here? Have you any free time and hobbies? What is your yearly income again? 🙂

Nice job.


Bruce