iBook G4 1.33 Ghz - Boot Problem

craigymusic

craigymusic

Registered
I was given a 1.33 Ghz 12" iBook. I have been working on it for some time. The start up chime sounds, the usual whirring sound happens and then it either boots normally, or stops at a black screen at that point. It is quite random. I have changed the hard drive, I have tried two different logic boards: it still happens. The only other repair I have done is to repair the display cable. The repair involved finding which wire in the cable (of 4) was broken and soldering a new one in it's place and then re insulating it with tape. When it boots the display is perfect, all the ports work, the screen does not flicker if the lid is moved etc. I have taken out the extra RAM, and just used the built in RAM...it makes no difference. I don't know what to do next.

I should add that there is no video out if the computer stops at the black screen point- I suppose it has not booted up so it has not got to the point of powering up all the ports etc.

I have tried different batteries, and two different power adapters as well. When I say Random I really mean it is Random.

Thanks, in advance!
 
Hi
When it goes to black screen can you hear the hard drive working or is the machine off? Does the caps lock key light up at this point?
It sounds like a video problem to me, maybe another loose/broken wire?
Ed
 
Yes, I can hear the hard drive revolving, and the caps lock light is working. One strange thing is that if I press number lock (F6 on the iBook) the light is not coming on, but if I press F5 it does...Thanks for your reply.
 
Hmmm, yes it does sound like a video/lcd problem if the machine is still going after the screen is black. If you hookup a external monitor to video port does it show anything before the 'blackout'? The external video should become live at some point in the boot process.
Ed
 
He already said the video out didn't work.

I should add that there is no video out if the computer stops at the black screen point- I suppose it has not booted up so it has not got to the point of powering up all the ports etc.
Click to expand...
 
Hi, folks. The iBook boots fine sometimes, with everything working. Othertimes it starts to boot but does not go beyond the black screen- with nothing working. I can hear the drive spinning, but that's it.
 
My guess would be a video or loose connection issue if the machine still responds when screen is black.
If you have another mac handy, you can turn on one of the file/vnc sharing options to see if its available on network while black screen.

Oh and greetings from across the ditch :)
Ed
 
Hi Folks, Some additional info/new behaviour...boots up to Open Firmware screen showing a system time of 01/04/1904 and 01:11:02!
Typing mac-boot brings up a flashing question mark folder.
The error message says Floating point unavailable then a symbol and SRRO: then the word deadbeec symbol SRR1 : 0000 1000
Can't start up in target mode, or single user, or from the Hardware / installer disc.

Edit: Symbol looks like a V with an S typed over it. Can't detect or ping on the network, by the way.
 
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Working on a customer's iBook G4 14". Original complaint was that it would only boot to the kernal panic alert. Tested natively and reproduced problem. All extraneous items removed -- including the battery and extra RAM. Reset the PMU (control-option-shift-power, wait 5 s, power up). Won't accept a Cmd-Opt-PR pram reset. Won't accept booting in open firmware (cmd-opt-o-f). Won't boot from external hard drive. Found this thread because the iBook exhibited the same behavior of F5 lighting the num lock light rather than F6 as it should. The caps lock light does work as expected. Machine will power up external Firewire hard drive.

I don't know if this is a botched firmware update by the customer, botched system update, failing hard drive or what -- but the F5-numlock light suggests bad firmware or motherboard failure in a very unique way and I cannot see how it would be related to fouled Tiger software since the OS doesn't even load at this point.
 
Finally got the machine to a bootable state. Battery out, unplugged. Power button down for 60 seconds. Power back in. Reset the PMU. Booted into firmware. Ran reset commands:

set-defaults
reset-nvram
reset-all

rebooted to external drive. Ran some RAM tests (rember). Noted F5 no longer lights num lock, F6 does. Still flaky. Will try replacing the internal hard drive in case that controller is failing and causing the motherboard fits. Really ugly.
 
I have fixed the problems I was having and now the the iBook is totally cool. The problem with it was to do with the built in airport/bluetooth card. The last revision of the G4 iBook 12" 1.33Ghz has this and it attaches to a socket on the logic board. In reference to the previous post regarding the 14" version the last 1.42 Ghz version has the same set up. The problem is that after a while, i.e. 3 years or so, the contracting and expanding of the area on the logic board where the socket is (which is right next to the heat sink) means that the card and logic board stop making the connection correctly. This generates a kernel panic if the computer is going. I suspect it causes all the other booting problems as well. I found several threads on other forums which describe fixes by shimming the plastic arm that holds the card in place-not the Corey Arnold fix- doesn't work. Neither does replacing the card- at least not with the logic board that was in my iBook, which suggests the socket itself has failed.
I noticed that if I booted the iBook into safe mode it never crashed. As safe mode disables Airport cards it was a fair bet that the Airport card had something to do with the problem. The crash reporter logs always contained the following information:
Thu Apr 16 21:31:53 2009
panic(cpu 0 caller 0x000A8C00): Uncorrectable machine check: pc = 00000000006B3548, msr = 0000000000149030, dsisr = 42000000, dar = 00000000E10A1000
AsyncSrc = 0000000000000000, CoreFIR = 0000000000000000
L2FIR = 0000000000000000, BusFir = 0000000000000000

Latest stack backtrace for cpu 0:
Backtrace:
0x000954F8 0x00095A10 0x00026898 0x000A8C00 0x000A7E90 0x000ABB80
Proceeding back via exception chain:
Exception state (sv=0x26487280)
PC=0x006B3548; MSR=0x00149030; DAR=0xE10A1000; DSISR=0x42000000; LR=0x006C8078; R1=0x0D0BBD30; XCP=0x00000008 (0x200 – Machine check)
Backtrace:
0x01727140 0x006C8078 0x002D1B8C 0x002D0A54 0x000A9714
Kernel loadable modules in backtrace (with dependencies):
com.apple.iokit.AppleAirPort2(405.1)@0x689000
dependency: com.apple.iokit.IONetworkingFamily(1.5.0)@0x5b6000
dependency: com.apple.iokit.IOPCIFamily(1.7)@0x48d000
Exception state (sv=0x20A67A00)
PC=0x00000000; MSR=0x0000D030; DAR=0x00000000; DSISR=0x00000000; LR=0x00000000; R1=0x00000000; XCP=0x00000000 (Unknown)

Kernel version:
Darwin Kernel Version 8.11.0: Wed Oct 10 18:26:00 PDT 2007; root:xnu-792.24.17~1/RELEASE_PPC

which was a further indication of the same issue.
Now I am using an Asus 167G wireless adapter and have 100% reliability with the same logicboard, hard drive etc.
I hope this information is of some use to my fellow mac users.
 
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