15" G4 Aluminum Powerbook starts up but the screen remains blank & the apple on back does not light up

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shocat's picture
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After a spill of Mtn. Dew on the keyboard of my Powerbook G4 15.2" Aluminum, 1.25GHz which I grabbed very fast (after the spill) to turn upside down while unpluging it & removing the battery.

I then took it apart (within 5 minutes), found next to no liquid inside, which was really suprising to me. I was only able to find a few (3-4) very, very small drops under the keyboard or surronding areas. I cleaned what was there and put it half back together (I left the screws out just in case it would not work).

Now it powers on and you get the normal chime, I hear the drives starting and am pretty sure it is up and running but the LCD screen is black or blank & the Apple on the lid is not lighting up either. The keyboard glowing lights work, caps lock works but I can't see anything on the screen, I have seen it flicker a very, very small amount on forced shut down once or twice.

What is the problem? The backlighting of the LCD? I want to guess this because the Apple is not lighting up as well. The LCD inverter? Or what? I am not sure so any help or suggestions would be greatly appreciated!

**NOTE** When the spill occured the Powerbook was on & in screensaver mode & I am positive that the Apple was NOT lit up right after I turned it upside down (to drain the liquid and remove the battery) but it was lit up right before that (during & right after the spill before I turned it upside down).

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......woops!

uh oh!

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themike's picture
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did you make sure everything

did you make sure everything is plugged in well?

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iantm's picture
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15" aluminum

Do you get video from an external video source? Can you tell if there is video on the lcd, albeit not backlit?

I would disconnect everything from the logic board and reconnect it. Chances are that your backlight cable may be loose, or if you've already done this, you may have mixed up the backlit keyboard and backlight connectors (they are the same on the aluminums). The lcd backlight connector is closest to the lcd, the backlit keyboard's connector is closer to the battery bay.

I've actually made the cable placement mistake. If you need any more help with this or need parts at a reasonable price, pm me. I may be able to help.

-iantm

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shocat's picture
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did you make sure everything is plugged in well?

yes cheched & double checked!

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shocat's picture
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15" aluminum

No video from the S Video out but as I am new to Mac's I do know with Windows XP the video out usually needs turned on before it can be used. I have not tried an external monitor yet.

I have unpluged every wire, connector & what not from or to the logic board. I can't see getting the two connectors (you spoke of)confused because the one furthest from the battery (the LCD backlight connector) is not long enough to connect to a different or wrong connector.

I have also zapped or reset the PRAM with the key combination at start up but nope still the same result.

I really have no doubt it is up and running it will take in a CD (but I pull it out before its all the way in) & + after the normal amount of startup time the keyboard lights come on, the drives are making there normal noises.

Here is a thought or question since I am positive the Apple & LCD was lit prior to turning it upside down & then once upside down the Apple went out (I imagine the LCD went out at the same time)...Might it be that some Mtn. Dew got behind the screen (while I flipped it upside down) causing this problem and if so what is behind the LCD that would or could be damaged by a liquid?

I will try an external monitor later this evening and report back what the result is! Thanks for the response, ideas and your time!

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iantm's picture
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Try resetting Open Firmware

Another trick to take is this. Hold down Apple, Option, O, and F. then type reset-nvram (and press enter), then type reset-all (press enter). Computer should reboot. After this, reset pram. It's possible that the video subsystem of your logic board may be damaged. Using an external monitor should help a good deal as it will tell you if the issue is with your logic board or lcd. Based on what you're describing, my vote is that your logic board is fried, assuming no video on an external monitor,

-iantm

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shocat's picture
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Try resetting Open Firmware

Ok here are three things

#1 I purchased the Powerbook used without the discs & I just now realized that the only piece I am missing (other than the software & original box) is the monitor video out converter, so no testing with an external monitor is possible right now.

# 2 I could not get the open firmware to work but I also can't see the screen, its pretty hard to do blind.

#3 The person I bought it from was not the original owner but was the second owner (so I was told). I paid $1175 for it with a very nice case 3 batteries (one is bad which I just learned is covered in Apple's batt. replacement program) & an external 30Gb hard drive. The Powerbook also has several expensive programs on it which is really why I could not pass it up.
Now I just checked the serial # on Apple's web site and it is under Apple care warranty for 445 more days. Since I am not the original owner what should I do to take advantage of the warranty? I have never delt with Apple on any matter let alone warranty work on a Powerbook that I bought used.

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BDub's picture
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Re: Try resetting Open Firmware

shocat wrote:

Now I just checked the serial # on Apple's web site and it is under Apple care warranty for 445 more days. Since I am not the original owner what should I do to take advantage of the warranty? I have never delt with Apple on any matter let alone warranty work on a Powerbook that I bought used.

Applecare does not cover abuse.

Spilling sugar water down the guts of your computer, then disassembling it and having it not work afterwards counts as abuse.

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shocat's picture
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Dissapointed on the lack of usefull knowledge here

I recently I posted a question-

15" G4 Aluminum Powerbook starts up but the screen remains blank & the apple on back does not light up

I just want to say I am very suprised not one of you Apple/Mac people could give a newbie like me (to Apple/Mac) the right suggestion or solution to my problem. None the less I figured it out on my own and it goes like this:

#1 & It gets no easier than this folks, all I had to do is hold down the (R) key during startup this resets the LCD on these machines & low and behold the screen popped right on when it should + everything works fine!!!

So for one to MR. BDub obviously I can spill suger water down the guts of my Powerbook, take it a part put it back together and have everything fine & it not be considered abuse (as long as you do it right or do the right things) The Powerbook was not broke & I really did not think it was.

I do want to think themike & iantm for your suggestions & tips as I do really appreciate it!

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iantm's picture
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You're welcome, and very interesting

I'd never heard of that trick before. Thanks, you just showed me a handy trick I'll be using in the future. Though, I always find that I learn something new every day. Though, when I think I've seen everything, I quickly learn that I haven't.

-iantm

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I'm going to try this....

I didn't spill anything on my 12" powerbook, but this morning I was using it and it just stopped working. The mouse was still moving the cursor around, but I couldnt' click on anything and there was no indication that it was "working" on something.

So I eventually shut it down manually with the powerbutton (which I HATE doing), and when it started back up, after resting for a bit, I just get a blank grey screen. I can't tell if it's booting without a screen or not, or if it just isn't working at all.

Ugh. I'm even getting ready to buy a new one, but really need to transfer some data from this one. Oh... I'll try the "R" button trick and see if it works for me. Smile