Dropped Powerbook - help with issues please

Hi All - I just purchased a 12" Powerbook G4 1.33Ghz as parts for a fun repair project. I received all parts except for the hard drive. The powerbook was dropped on the front-right-bottom corner (battery bay) ... it seems to have hit the floor perpendicularly, and amazingly enough, there was no dent or damage to the LCD. I massaged out the dent and it's fairly decent now and the battery fits in fine. Now I'm on to attempting to fix the powerbook to make it operational.

Observations:
- powers up fine
- I hear a chime
- I hear the hard drive spin up (I put in a new, known working hard drive) - I also hear data access to the hard drive, and without a cd or dvd in the drive I get the mac folder icon switching between the mac folder and the ? folder
- reset PRAM (command-opt-P-R) and NVRAM (command line)
- lcd works fine
- no hums or hisses
- battery charges fine
- power port lights correct as orange when charging and green when fully charged
- combo drive works fine - bootup recognizes tiger install cd and techtool deluxe
- boots into techtool deluxe fine
- does NOT boot into the Tiger OSX install screen - it finds the cd to boot but it stays stuck on the Apple logo screen with the spinning color wheel constantly spinning
- trackpad and trackpad mouse works fine
- keyboard works fine

Symptoms
- techtool deluxe hangs while "searching for volumes" - the icon shows "Pending - Processor" with a picure of a micromat processor image
- it's not truly hanging, because I can still click on start/stop and all the menu items on the top (Apple icon, File, Control, Services, Window)

I haven't reset the PMU yet, but that's next, however I doubt it'll fix the issues. I haven't switched out the memory module yet.

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Any experience on the symptoms? Any suggestions on what is wrong? It seems the video GPU works fine... the processor has to be working in order for it to even boot or recognize the cd/dvd and boot up into the software, but it is odd that the techtool program hangs when trying to find volumes.

It sounds like the hard disk controller is damaged? I don't understand how the fall would have damaged the controller only but not the other parts of the logic board. Perhaps I plugged in the hard drive into the logic board incorrectly?

NOTE: I've never repaired a powerbook before, but I've repaired numerous other windows and ibook G3 laptops.

Thanks for reading!

another note, upon booting, I cannot get into the single user mode with command (apple) - s.

When I try command-s on bootup, I get the mac folder and ? icons

But this is the same as if I didn't press any buttons on startup... so I'm not sure this would indicate that the hard drive is bad...

Put os x on a firewire drive.

Boot up from the fire wire drive, or what you could do is make a bootable copy of linux. Out of curiosity, how much did you pay for the powerbook?

thanks for the tips!

UPDATE: Apple Hardware Test v2.5 (finally got a copy of one) ran completely fine on the machine, both regular and extended versions. The AHT doesn't run tests on the hard drive or hard drive parts, so perhaps that's why it passed correctly. The same Powerbook G4 Install/Restore CD set booted up correctly, but it said the restore "...could not be installed on this machine" (???) but the same install set works fine on my 12" G4 1.5Ghz powerbook.

OSX Startup Disk recognized my hard drive, so that gave me hope... I swapped in an old hard drive (with an existing Tiger installation) I had from my iBook G3 900Mhz machine, and the powerbook booted up without a problem! (I didn't know hard drives were swappable between different generation processors and speeds! This definitely beats Windows computers and compatibility Also makes it easier for software piracy!!!)

So I still have problems getting Tiger Install disks to boot up on the machine, and TechTool Deluxe can't get past the "scanning for volumes" test startup... but the computer runs flawlessly if it has a harddrive with an existing OSX installation!

I guess I'll have to make sure I have a backup hard drive with OSX installed in case the hard drive ever goes bad... but I guess it might be hard to upgrade to Leopard in the future. I've verified that a Carbon Copy Cloner imaged hard drive swaps in and boots fine!