After 12-14 hours of troubleshooting and forum crawling I have no option left but to throw in the towel and ask for some help, the situation is as follows;
I've had a 512mb Jasper for quite some time now with a liteon 93450c drive I assumed was dead (Open tray error). I dumped the firmware from that drive using the MRA hack, and then purchased a new 93450c drive from eBay when one became available.
Upon recieving that drive the first thing I noticed was that the original drive information had been covered by a new sticker, along with the part and PLDS numbers, the old drive info said the drive was a liteon 8 series and the new said it was a 9 series. Naturally I was suspicious and so hooked up JF, I got a 9 series reported however when I went to flash the drive with the firmware from the old drive I got a warning about the F/W not matching the drive revision. I try to be cautious about these things so I stopped and performed the MRA hack on the new drive as well, dumping and retrieving it's original firmware and key. Now what's interesting is that the dumped firmware's barcode matches the original
barcode and that all serial information is missing. When opening this firmware file JF would give a warning and ask to repair the serial data, which I did and created a new file - fixeddummy.bin
Now on to where the fun begins, as I mentioned before the original drive already exhibited the 'Open Tray' error, and so after a short time I decided it was gubbed and purchased a new one, now having dumped both original firmwares and repaired the traces I flashed the fixeddummy.bin to the new drive after manually spoofing the drive key, the OSIG already matched so I didn't worry about that. When I re-attached the drive to the Xbox it would spin, click a few times, spin again and then display "Open Tray". Now I was really
stupid and didn't test this drive when I recieved it, however I thought, "lets try the original firmware, see what happens". JF gave me a warning that the backup didn't match the drive's serial info, I ignored this, erased to get into vendor and then attempted to write the original dump.
At this point JF locked up completely, and not due to the usual causes (drives were not installed, using main internal SATA port on a Via 6421 chipset) but rather JF ONLY locks up when writing this particular firmware. I was able to write the firmware to the drive using DOSFLASH v1.7, again though when I put the drive into the Xbox 360 I got the same issue, except no spinning, no clicking just straight to 'Open Tray'. I thought at this point perhaps the laser had gone, so I removed the drive cover and the laser seemed to be firing fine, and the drive would attempt, for a very short period to spin the disk before giving up.
This seemed indicative of a badly configured potentiometer I thought, so I attempted the infamous pot tweak going from 6.5k to 3.5k in 0.5k and then 0.2k increments to no avail.
I've triple checked my PCB soldering and it seems fine, no shorts and everything that should be connected is giving a glorious 'beeeeeeeeep' on the multimeter continuity test
I'm currently in the process of uploading a high-res video to YouTube which I wll append to this post, showing the soldering, the problem with the drive in the Xbox, the error JF gives along with a general picture of my despair as this Liteon slowing eats hours of my life :/
Anyway guys I know the best of the best are on here, so any suggestions for what I could try I'd be more than happy to oblige, I've just been fortunate enough to come into the possesion of a high-res DSLR so if you require pictures of components/soldering work I'd be happy to oblige.
As usualI did peruse the forums extensively and whilst there are plenty of "Open Tray" threads none seemed related to my problem, hence the new thread creation, my apologies if I somehow missed a similar one elsewhere.
All the best.