15" AlBook G4 Won't Power On

[CC_333]

Hi,

I just got a 15-inch Aluminum PowerBook G4 today. Judging from the sticker in the battery bay, it is at least an early 2005 model (I can't tell exactly if it's the Hi-Res model or not) running at 1.67 GHz.

However, it doesn't work! It won't power on, there's some case damage on the front left corner, and the battery is dead.

The indicator on the adapter (genuine Apple, not generic) lights, and it goes amber for awhile, which suggests that it's trying to charge the battery. But nothing happens when I press the power button. Not a thing. No sound at all. It's as if there's no power.

Does anybody know what might cause something like this? Not knowing better, I suppose that it could somehow be related to the logic board, or, if I'm lucky, a separate power-related board which is both easy and inexpensive to replace.

Hopefully, someone out there has some information which can confirm or debunk this supposition.

c

Edit: I did some research on this machine, and apparently it is not the Hi-Res model, which is kind of too bad. I also found that it has a separate DC-in/Sound board which could be bad. That means that the logic board is probably OK (although I cannot say that for certain until the DC/Sound board is tested and repaired/replaced.

 

[beachycove]

Remove the battery, unplug, press power for a few seconds, then plug in again and press power on. Then, if it boots, try installing the battery and see if you get a charge (probably not).

Won't boot with a dead main battery.

 

[CC_333]

Remove the battery, unplug, press power for a few seconds, then plug in again and press power on.

If you are referring to the PRAM reset procedure, I've tried that a couple times.
I've also tried booting without the battery, with no change in behavior.

The person from whom I bought it said that he was using a 3rd party AC adapter, which shorted out at some point. The computer, he said, would not turn on after that.

Do you think the DC-in board could cause symptoms like this if it were damaged by a short?

Thank you,

c

 

[bibilit]

One of my clamshells had the same behavior, i get an amber light but nothing more, the adapter was tested and i did get the right voltage...but obviously something was wrong with it (i tried with another one and the Ibook booted right away)

 

[CC_333]

Hi,

This is a known good adapter. It powers the Titanium PowerBook just fine, although it has mysteriously cut out on me several times (this is most likely due to overheating, because it doesn't happen in cooler weather, nor when I ease off on any heavy duty processing).

I am currently disassembling the machine to get to the DC board. I will then examine it and see if it can be repaired, asking you all questions accordingly. If I determine that it's not repairable, I'll replace it.

If the DC board isn't the problem, then the only other component which could be at fault is (gulp) the logic board, which unfortunately isn't cheap (unless I want to take a risk on an untested as-is piece from eBay).

Wish me luck!

c

 

[spiceyokooko]

The machine should still boot with the power adapter plugged in even though the battery is bad, although, if the battery has been allowed to drain to nothing you may have problems. It will not boot with the battery out and the power supply plugged in. The psu unit for the Titanium and later Alu models is the same wattage - 65w so that should still work okay.

Try resetting the power management unit - hold the power key down for at least 6 seconds, let go then press once, if it still doesn't boot, reset the PMU from the logic board. The PMU on the logic board can be reset by bridging the two small pads with a flat bladed screwdriver. This is located on the logic board just above the track pad area to the left of the optical drive. There's a cable that runs along this area look there for the 3 sets of two pads, separated by a fine white line. There's 3 sets of 2 pads, one resets the PMU, one resets the PRAM and one allows you to boot the machine without having the top-plate and power button installed.

I'll email you some information that will help you locate these areas.

 

[beachycove]

The machine should still boot with the power adapter plugged in even though the battery is bad, although, if the battery has been allowed to drain to nothing you may have problems. It will not boot with the battery out and the power supply plugged in.

I have the same machine here in the house and have twice had to resolve these symptoms. It won't boot with a dead battery and it boots just fine with the battery removed. Once running, if you pop the dead battery in, it won't wake from sleep. Stick a good battery in and all is well.

 

[spiceyokooko]

I've just checked the Apple Service Manual for this machine and you're right, it will boot with the battery out - but ONLY if you're using the correct power adapter - which ccc isn't.

However, resetting the PMU should be the next step really.

 

[CC_333]

Hi,

Well... after a complete teardown, I think I have discovered the problem. A chip near the DC-board connector on the logic board is blown up. It's burnt, and a big chunk of the housing got blown away. So this logic board's a lost cause, I'm afraid.

Well, now I have a bunch of parts anyway!

c

 

[spiceyokooko]

Shame!

Keep your eye open for a parts machine on eBay with a busted screen/busted case/missing RAM/HD etc. and hope the logic board is good.

Don't bother with the 'sold as seen and untested' logic boards you find on eBay, it's odds on they're faulty. Sold as seen and untested is eBay speak for - this don't work. I would take a risk on some 'sold as seen' items (RAM for example) but not logic boards.

The only way I'd buy a logic board on eBay is if it's sold as 'tested as working' and has a DOA warranty on it.

 

[CC_333]

Hi,

Thank you for your advice, spiceyokooko.

I have a plan in the works for getting another model A1106 PowerBook, so hopefully it has a good logic board (I don't really care about anything else).

Shame!

It is a shame, since this was the 1.67 MHz model. Hopefully I'm lucky and this other PB is also 1.67 GHz. I can live with 1.5 GHz though.
Thank you,

c

 

[spiceyokooko]

Ahh the low res one.

I have a high res and low res 1.67, 17 inch and to be honest there's not really a lot of difference between them that I can tell. The most obvious difference is the the higher resolution screen, which I admit is useful but only if you use the laptop as a laptop! I use both mine with a 20" Cinema display and external keyboard and both models display the same on the Cinema Display - the only difference is on the laptop screen itself. The RAMs faster in the high res but I don't notice much difference to be honest and the only other difference is that the high res comes with a 120Gb drive as opposed to a 100Gb in the low res - no big deal.

So if you're primarily going to use it on a monitor, I wouldn't bother with the extra expense of a higher res board.

I'm going to sell a couple of my 1.67 Powerbooks soon to finance a Mac mini.

 

[CC_333]

Ahh the low res one.

Yeah, it is. I was kind of hoping it was the hi-res model, but as I researched it a bit, I discovered that it isn't, but it is very similar as you pointed out.
That being said, is it possible to take the LCD from the hi-res model and install it on a low-res model without any funny compatibility issues?

c

 

[spiceyokooko]

Oh and the other difference is that the high res has a dual layer superdrive.

I honestly don't know the answer to that question.

Theoretically it shouldn't make any difference as they both use the same GPU, but knowing Apple there's probably some subtle difference that makes it impossible to use fit the high res screen. Apple are renowned, or should I say Steve Jobs was renowned for making it awkward and difficult for end users to get inside and upgrade the machines themselves. He detested the thought of someone getting inside and altering the perfection he felt the machine should be. In other words he ordained you to have what he wanted you to have and not necessarily what you wanted to have!

 

[CC_333]

Theoretically it shouldn't make any difference as they both use the same GPU, but knowing Apple there's probably some subtle difference that makes it impossible to use fit the high res screen.

Maybe... I think this issue needs further research and testing!
Anyway, my hope is that this machine can somewhat more easily handle playing back semi-modern video formats without overheating (as the Titanium does), since it also has an S-Video port. The extra .5 to .67 GHz should also help in this regard; since 1 GHz, given the proper conditions, can play such videos almost flawlessly, then it should be no problem for 1.5/1.67 GHz!

Maybe I can try finding a broken logic board and transplanting the blown chip. It's not terribly likely that any board I get will have the same problem as mine, is it? It's probably just simpler to use it for parts.

Anyway, hopefully I can get the other A1106 tomorrow. Between the two of them, I should be able to make something work. And I've learned a lot by disassembling this broken one.

c

 

[mcdermd]

The extra .5 to .67 GHz should also help in this regard; since 1 GHz, given the proper conditions, can play such videos almost flawlessly, then it should be no problem for 1.5/1.67 GHz!

The faster RAM doesn't hurt either.

 

[CC_333]

The faster RAM doesn't hurt either.

Yeah! That's good too.
However, the difference in RAM speed between the low-res G4 and hi-res G4 is negligible in my opinion. The difference between even the slowest Aluminum G4 and the Titanium, on the other hand, is more considerable.

As I've said, I plan to cobble together a working machine using another parts machine which I hope to pick up tomorrow.

In the meantime, I am working on setting up (gasp!) a PC with a TV tuner card to serve the purpose.

To that end, does anybody know of a cardbus/PCMCIA TV tuner card which is Mac compatible?

I'll look around and see what I find.

c

 

[CC_333]

Hi,

I got the other machine (which is a 1.5 GHz model), and decided that since it was almost fully assembled anyway, I would just take the PRAM battery, hard drive, RAM, RAM cover and upper case screws from the old machine (because they were all missing and the hard drive was dead).

I think the lower memory slot has failed unfortunately, but it's working great otherwise! I am writing this on it now, in fact.

I may take the display/lid from the other one, because I think it may be in better shape cosmetically, but it works for now!

I just need a new battery, and I'm all set!

Thank you all very much for your help!

c

 

[CC_333]

Hi,

I've taken the display assembly from the parts machine, and it is noticeably better.

However, I have now lost the ability to sleep the computer by closing the lid. Why is this?

The parts machine was a 1.67 GHz model, while this one is a 1.5 GHz (both supposedly A1106). Is there some kind of internal difference which may be causing this?

The alignment is slightly off, too, but I doubt that would cause this problem.

Thanks,

c