[Captivate Q&A, Help & Troubleshooting] davenz:
Hi team. I've searched the forums for answers and even though I've read a thousand excellent posts, none (of course) fit my situation specifically. I'll try to be as brief as I can.

My AT&T-branded, Chinese imported Captivate was only three weeks old when I first soft-bricked it trying to do an update using Kies (thanks Samsung!) and then because it would only go into download mode, I tried using Odin to reflash back to where I was. The flash didn't take and I was left with nothing; no charging icon, no computer recognition (Windows 7 Ultimate 32-bit using the generic Samsung Android phone drivers downloaded from somewhere on XDA) and no boot/download mode; in other words, hard-bricked and nothing working.

I bought myself a riffbox and spent a long time reading various forum posts about using it; I own a computer repair company and have flashed a million motherboard, modem, router and other firmwares over the past 15 years and have even done a Samsung S2 and a Galaxy Pad in the last week so am reasonably comfortable with the process, even though I'm not hugely experiences yet with the riffbox.

Anyway, I imported and soldered the recommended panasonic socket to the JTAG point and made myself some PCB adapters to fit and break out the Riffbox cables. That's all done and dusted and today I used the Riffbox on my Captivate for the first time, apparently detecting the 'dead body' and flashing the ROM successfully (the box and software would soon tell me if something wasn't right). While I hoped it would, I didn't expect my phone to boot straight away, but did expect it to go into download mode, as suggested in the JTAG literature with the Riffbox. This is where it all gets bent out of shape.

I always get into download mode with my Captivate by dropping the battery and then replugging with the Vol + and - buttons held. I have tried all methodfs I can find on XDA but all either don't work or do the same thing, that is, my phone enters download mode for about ten seconds, then drops out again. During that time, all USB devices 'hang' while the computer tries to fathom what the hell is connected there and Andy just holds his shovel and laughs at me before disappearing once again into the inky blackness of a dead screen. The device manager shows an unknown device detected before letting it go again and mouse and keyboard control resumes. Weird. I thought it might be a flat battery but I've charged that so it has plenty of juice. When plugged via USB, there is 4 volts at the battery terminals (measured with the battery out) so it would charge when plugged in (wall wart or USB cable) even though no icon shows.

Like any good tech I went back and reflashed using both the recommended ROM and 'last resort' option in the Riffbox (Clone Gremlin Zone flash) and the phone still does the same thing; enters download mode then off. I made up a USB dongle/jig using exactly 301 kilohms of resistance (measured digitally) across pins 4 and 5 and followed the various videos/explanations to get into download mode that way but this does not work on my phone, leading me to think something else is broken.

Bottom line is that it seems the phone doesn't have to be connected via USB to enter download mode but if Windows cannot load the phone, then I cannot use Odin or Heimdall to reflash it. I don't think it is drivers because it worked OK before the brick (well, not perfectly but it did connect and I had USB drive support etc.) and besides, I have tried reinstalling drivers to no avail. Can anyone suggest anything I can try (shipping it to some guy in the USA is not the answer I'm going for here so please don't waste your time or mine). As far as I can see, I have done everything the people here suggest and the JTAG/Riffbox instructions to the letter but it just does not want to happen. I'd rather not lose the phone and since I eventually want to offer this sort of service in my business, I want to get it to work on my own phone for my own pride and knowledge.

Cheers from Christchurch New Zealand.