Operation Katsutoxin: Samsung Galaxy Tab GT-P1000 - Boot from External SD (Part 1)

I was asked to fix a Galaxy Tab P1000 which stucked at Samsung boot logo. At first I thought it was just a simple file system corruption where flashing a factory ROM will get the job done, but it's not that simple.

As usual being an ORD I rebooted the Tab into recovery mode but was greeted with mounting error. Factory resetting did not help so the next logical step was to fired up Odin and started flashing the latest Gingerbread for the Tab, and (of course) Odin failed to complete the process. When I tried to restart the Tab, what greeted me was the infamous black screen of death!

I've seen that on my i9000, luck was on my side back then but not this time. Still, I was extremely excited because it's a chance to try out the unbrickable mod! The hardware mod is required to resurrect the device to enable the processor booting from USB, and a software can be used to boot the Tab into Download mode. I was excited because the Tab has the same Hummingbird ARM Cortex-A8 processor as my i9000, which I have no courage to apply the mod.

Further Googling my friend and I came to a deduction that the internal SD of the Tab has failed, where symptoms were similar to what described in this page. The way to fix this Tab is to first resurrect it from the black screen of death, and then modify a custom firmware to mount the /data, /cache, and /sdcard partitions on the external SD.

First step, ifixit time. With the help of another friend (and without referring to ifixit), we opened up the Tab.

Back casing was the hardest to remove to preserve cosmetics. The failed internal SD - SanDisk NAND Flash IC rest under the GT-P1000 sticker, which is strangly not covered by EMI shield (maybe it's the reason it failed so easily?)

Battery removed:

The processor and the xOM5 resistor sit under the EMI shield which was secured with screws from beneath. We had no choice but to take out the main board to remove the EMI shield: