Sounds like the "reed switch"
I just had almost the exact same problem with an iBook that I believe had been dropped. The dead give away was in system profiler - at the very bottom look to see if it says "
Clamshell Closed: Yes" if the lid is obviously open and it thinks it's closed it will cause a whole host of problems.
Reed Switch details:
http://listserver.themacintoshguy.com/pipermail/iBook/2004-August/010663.html
A reed switch is a tiny glass tube with two metal reeds inside that
almost touch. Normally, current cannot pass through the switch because
the metal reeds are separated by a small gap. When a magnet is brought
near the switch, the reeds are drawn together toward one side of the
tube. They make contact, and the switch turns on.
(Credit due to Justin Granger at smalldog.com posted via link above)
In my case the glass tube around the reed switch was shattered and causing an electrical short...I actually got a tiny shock from current still in it after it was taken it out completely. Unlike other information I found online, my reed switch was located on the bottom casing around the CD-Rom drive/under the keyboard (so I didn't need to take the display casing completely apart). Once the iBook was all back together it worked flawlessly, backlight, keyboard and touchpad were all working again as expected. The only downside is, the iBook will never go to sleep when the lid is closed b/c it won't know any better...but I don't care it was a free iBook
all I had to do was get it working and the reed switch is not required for operation otherwise.
I originally came to this forum for help before I figured it out and was going to post my troubleshooting thus far, but after concluding the reed switch was the problem I figured I'd wait until I knew I was right before posting my original post details are included at the very bottom, hopefully they'll help someone else diagnose this problem as before I figured it out, I didn't even know what a reed switch was.
Other info I found/used
http://schwarztech.us/articles/ibookcable - picture/info on reed switch problems (not mine)
http://www.macrecycling.com/images/products/922-6932.gif - picture of my
http://forums.macrumors.com/showthread.php?t=124449 - someone else with reed switch problems
http://www.powerbooktech.com/knowledge,type-6.htm - diagram on iBook dismantling
If you are comfortable taking apart your iBook and it is already out of warranty proceed with caution and Good Luck!
If your iBook is still under warranty or you can't afford a new one if the repair ends up breaking it more, leave it to someone that has experience or contact Apple/a professional...unfortunately the reed switch is likely an expensive repair to let Apple/Other certified repair place do b/c of the labor even though the part alone can be purchased for somewhere between $15-$100 depending where you get it or it can just taken out. Please do your own price/risk research before making a decision as this is merely my opinion and I do not work for nor am permitted to speak for Apple or what they actually charge for repairs.
Last login: Thu Aug 23 13:37:35 on console
Welcome to Darwin!
crap-ibook:~ crap$ system_profiler
Hardware:
Hardware Overview:
Machine Name: iBook G4
Machine Model: PowerBook6,7
CPU Type: PowerPC G4 (1.5)
Number Of CPUs: 1
CPU Speed: 1.33 GHz
L2 Cache (per CPU): 512 KB
Memory: 1 GB
Bus Speed: 133 MHz
Boot ROM Version: 4.9.3f0
Serial Number: 4H6095HBSE7
Sudden Motion Sensor:
State: Enabled
Version: 1.0
(in between stuff removed)
Power:
System Power Settings:
AC Power:
System Sleep Timer (Minutes): 0
Disk Sleep Timer (Minutes): 0
Display Sleep Timer (Minutes): 0
Dynamic Power Step: Yes
Reduce Processor Speed: No
Automatic Restart On Power Loss: No
Wake On AC Change: No
Wake On Clamshell Open: Yes
Wake On LAN: Yes
Wake On Modem Ring: Yes
Display Sleep Uses Dim: Yes
Battery Power:
System Sleep Timer (Minutes): 5
Disk Sleep Timer (Minutes): 5
Display Sleep Timer (Minutes): 5
Dynamic Power Step: Yes
Reduce Processor Speed: No
Automatic Restart On Power Loss: No
Wake On AC Change: No
Wake On Clamshell Open: Yes
Wake On Modem Ring: No
Display Sleep Uses Dim: Yes
Reduce Brightness: Yes
Battery Information:
Battery Installed: No
AC Charger Information:
AC Charger (Watts): 50
Connected: Yes
Hardware Configuration:
Clamshell Closed: Yes
UPS Installed: No
Original troubleshooting/intended post:
sounds pretty similar to the problem I’m having….got this laptop from work as a challenge to “play with” so I don’t exactly know the whole history of it, but it’s rumored to have been dropped, but I’m having trouble really isolating the hardware problem from the software (it acts like both). When I first got it, it would boot up, but show nothing on the screen/no back light until the blue screen before login, could login and have just enough time to open system prefs and then it would go to sleep (30sec - 1min or so I’m guessing) after it goes to sleep I can wake it up with option or command (have to hold it down for a bit) but when it wakes up I have no backlight, and the keyboard doesn’t work (but the iBook will work with an external monitor if the monitor was connected during startup) with the external monitor I can continue controlling the system for about 30 seconds at a time via the trackpad mouse but I have to use a USB keyboard (which is still hot swappable as it should be unlike the monitor) there is nothing I can hold down or do that I’ve discovered so far to keep the iBook from going back to sleep making troubleshooting quite slow and tedious.
- Found that keyboard & backlight physically work fine, can clear PRAM on startup and use option startup or c to boot to CD/DVD and run Apple Hardware test (which came up clean)
- Can clear nvram in open firmware, and iBook stays on for hours without going to sleep and backlight and keyboard physically work fine.
- After booting to random 10.4.2 disk that I’ve used several times in the past it didn’t recognize the lcd so had to use external monitor, but I could successfully install 10.4.2 after also plugging in a USB mouse (it demanded it and halted until I plugged one in) full format install probably rules out any HDD physical damage since I’ve formatted it 4-5 times by now on boot up after install it didn’t recognize the iBook lcd at all (like not even in system profiler) so had to use external monitor, USB mouse and also USB keyboard after finding iBook didn’t recognize it’s own keyboard and still not the trackpad….but the sleeping problem was gone YAY! Except a laptop that can’t work “undocked” is useless.
- Found some original iBook G4 10.4.2 and 10.3.7 restore disks we had laying around at work, it treated the panther set like my generic tiger disk so I didn’t bother to install and judging by the serial number this was made 9th week 2006 so it would have shipped with tiger anyway…booted up to the tiger restore and iBook seemed quite happy, I had backlight, and trackpad but no keyboard, after running updates and upgrading to 10.4.10 it was back to its original tricks – no backlight until blue screen, keyboard an mouse work until it goes to sleep about 30 seconds after login.