400mhz G4 TIbook - startup chime, but no video.

T

twisted creek

Registered
Hello folks.

I have a 400 mhz Titanium powerbook I'm trying to resurrect for my teen daughter. Just replaced the internal pram battery, the external regular battery, and the a/c cord, all with brand new parts. The book was dead, and now I have power but not much more.

When pressing the power button I get one chime, and then I can hear the fan working, but no hard drive sounds. The screen is black.

Eventually, when left sitting, the thing will turn itself off. It seems as if it is not booting completely, but then I can't see anything. I am used to hearing hard drive pops and whirrs though, and nothing here.

1. I tried resetting the PMU with the button on the back of the unit.
2. I tried resetting the pram with cmd/opt/p/r before power, but no matter how long I hold I only ever get one chime.
3. Tried booting with my OS Tiger retail CD (which is what is installed) and the drive barely spins, and the screen remains black. Holding C doesn't help.
4. The new battery is charging normally.
5. I tried removing the two ram sticks, moving them around from slot to slot, and using one ram or the other. Nada.
6. Tried forcing shutdown by holding power button 10 secs, then rebooting. In fact, that's how I have to shut it down when I need to, since I can't see anything.

This laptop has been in storage for about a year. This is the same problem I had when I put it away. I think perhaps the laptop might have been knocked off the coffee table and fell about 2 feet to the floor a short time before these problems. I heard it, but the kids won't admit it. *grin* It worked fine for about a week or so, then began losing video at startup.

I just spent about $75 in parts. Should I maybe try a new PMU board before chucking the thing? Any other ideas what might be happening?

I've read till my eyes are blue, and can't seem to find a boot issue with one chime on this machine.

thanks for your help!

rebecca
 
Hi; One beep at startup means that your ram is not being recognized.If your battery is charging then the pmu should be ok.More than likely your logic board has gone out.Finding a new board is next to impossible and if you do the cost will be very high.You could get this pbook going again but between what you've spent already and a new board,you could pick up another used one on Ebay.
good luck!
 
Hi; One beep at startup means that your ram is not being recognized.If your battery is charging then the pmu should be ok.More than likely your logic board has gone out.Finding a new board is next to impossible and if you do the cost will be very high.You could get this pbook going again but between what you've spent already and a new board,you could pick up another used one on Ebay.
good luck!
 
Thanks for replying *smiling*

There's no "beep" at startup, it's the regular Mac startup chime, or chord. It seems like it is beginning the startup normally, but hangs after the chime with no video.

rebecca
 
Hi;Had to dig out my service manual for this machine.Here is what Apple says,
1.Verify inverter cable and lvds cable connections are seated properly and that the cables are not damaged.[this could have occured during a fall]
2.Replace inverter board.
3.Replace display assembly.
4.Replace logic board.
You can check to see if you still have video by shining a bright flashlight close to and at a slight angle to the screen.You will see a ghost image if video is present.
I hope this helps!
 
Thank you so much. I took it apart using the guides at powerbookmedic.com, and re-assembled, checking to make sure all boards were seated properly, and all things plugged in tightly.

Booted it, and it works!

I appreciate the time you took to help me. Just wanted to come and say thanks...

rebecca
 
You must log in or register to reply here.
Back
Top