PDA

View Full Version : Dying iBook...Maybe not?



paulbc
16th March 2010, 06:24 PM
I would love to save my 14inch G4 ibook(OSX 10.4.11)...it's lasted 5 years without a hitch.

But it has some behaviour problems...

Recently it would only turn on with the fans blasting. We did a PRAM reset (apple, P, R) and it started! Then it went back to fans after we shut it down.

An ex-Apple tech mate told me it could be the PMU (power management unit), so i reset that(SHIFT, control, option, Power)...and the fans still came on on startup...black screen...nothing more.

So, then...and this is the best part.

My wife had recently put an Excel worksheet on the computer for work...it had macros and all sorts of wacky stuff...she swore black and blue that the computer had crashed not long after putting the file onboard.

I scoffed. As a husband does...

A microsoft program couldn't possibly upset OSX that drastically.

Anyway, scoffing aside...

It miraculously booted up after a random(and I mean random) combination of (safe mode startup[hold SHIFT key]), PRAM reset, PMU reset (hey, I threw everything at it!!). So I dragged anything of importance onto our backup drive and then proceeded to play around with it whilst it was breathing.

I deleted the Excel spreadsheet...just to satisfy my wife.

Shut it down successfully.

Started up successfully.

Shut down again (must have been a fluke right?)

Start up fine. (shit...now I have to admit I must have been wrrrr....wrrrrr)

BUT!

She's still not quite right. (the ibook that is...wife is always right from now on)

Now it will hang at random times.....screen on, but frozen.

Can anyone explain the riddle?

I'd like to know if I can keep it for the kids...with of course, a diligent backup regime. (store all their files on the network rather than on the ibook)

Look forward to any suggestions...or if not, buyers.

cheers Paul

iMic
16th March 2010, 07:50 PM
Nice riddle, and i'm going to take a shot at solving it. :D

I'm guessing at this point, with the startup issue at least (since it occurs before the OS is loaded), we can at least somewhat rule out software. Apologies if this assumption is incorrect. Also apologies for the wall of text to follow.


My old iBook (1.07GHz, 12") exhibited the same issues. It occasionally started up to fans on full with no display or chime and occasional complete system lockups at random. The computer wouldn't register a fault with the Apple Hardware Test or Techtool Pro.

I did some searching around when mine did this and found two points of failure on the iBook G4.

The first point of failure is the connection between pin 28 on the Vreg chip and the logic board. A failure of connection often results in no video output on startup, no chime and the fans run at full power until the system is switched off which sounds like the symptoms you described. In addition if the connection is broken while the system is running, the screen will blank out altogether. The repair instructions for this one can be found here. iBook G4 Logic board repair (Vreg chip solder joint repair) (http://www.xlr8yourmac.com/tips/iBookG4_vreg_repair/ibookG4_vreg_repair.html) Most electronics shops could probably tackle that one.

There's also one other issue I was alerted to by another MacTalk forum member that could cause issues, and that's the solder under the GPU cracking. This apparently accounts for the random freezes. I've had success with a heat gun over the chip to fix this one, but it's a finicky repair and requires stripping the entire system down to its bare logic board to do. I think the kind of work required probably outweighs the value of the machine in this instance. It's possible someone would be able to fix it I suppose if they had the time, patience and tools.

My iBook had all of the symptoms and over the course of a week I managed to pull off both repairs. That iBook still works to this day as a result, rock solid (apart from being fairly scuffed up and missing a few screws).


Unfortunately with issues like this all you can really do is take an informed guess, any more info is certainly appreciated if it sways the verdict one way or the other. If you're lucky it could just be the first issue accounting for all of the symptoms or even something even simpler, hard to tell. At the moment i'm just going by past experience (I sometimes buy defective systems and attempt repairing them) and the assessment based on the rough symptoms of the issue.



Cheers :)

- Michael

Byrd
16th March 2010, 08:01 PM
Hi Paul,

I second iMac600's sentiments that the logic board is flaking out, and what's happened with Excel is just a freak of nature.

"The test" for a faulty vreg chip is to place firm pressure on the top and bottom of and region to the left of the trackpad; see if it fires up then and slowly ... take your hand or vice away ... see what happens. It is repairable with good soldering skills, but isn't infallible.

JB

wesleyong
23rd March 2010, 08:09 AM
Yup, my iBook did that several years ago. I opened it up and put a tiny piece of lego over that faulty chip and closed it all back up. Pretty quick and easy teenager fix!

Byrd
23rd March 2010, 08:15 AM
wesley: ah the old Lego trick! :)

On a similar note, I was given an iBook 1.07Ghz with the usual logic board issue. The previous owner must have had some old credit cards they used to place pressure on the vreg chip (and surrounds) on the logic board. Obviously it worked for a while - then flaked out, so more pieces of credit card were applied.

The grand total: eight pieces of credit card, piled high! The iBook couldn't sit correctly on a flat surface due to all the bulging on the underside of the case :D

Needless to say, I removed all the pieces, and resoldered the vreg chip: still not perfect, might have to go in again or perhaps the board was so flexed something else is out too.

JB