No power after baseband reball
Hi all, hoping for some inspiration from someone! Got an iPhone 6 which was working fine in every respect except it had the Searching/No Signal issue. No IMEI from #*06* and no Carrier entry in Settings, so I went ahead and removed the baseband ic to fit 2 jumpers. I got really good soldered points on the vias for the 2 jumpers and was pleased with the result; I then covered the area with green curable solder mask, cured it until rock hard, cleaned up the pads on the BGA and re-fitted the baseband chip. This all went fine, and when it was back on I tested all the caps in the vicinity for continuity and all were fine. However when I plugged it in it's drawing 0.00 amps . I tested both VCC-MAIN and BATT_VCC for shorts and the battery line was shorted. I then had a closer look around and found that one of the chips close to baseband (U_2GPARF) was looking a little crooked and may have moved while I was working there. I checked on PADS and found out that this ic has a direct connection from the battery connector, so I removed the ic, cleaned the pads, reballed the chip and put it back; BATT_VCC short gone. Plugged it back in - still 0.00A. Then I thought that as both Tristar and Tigris are right on back of the board from where I'd been working that the heat had maybe caused solder to flow and bridge or short, so changed both tristar and tigris. Plugged it back in , yep 0.00A! I'm beat now, I can't think of what else to try. I don't think baseband has any direct connections to power lines and that's all I did initially; and I'm not even sure that baseband is needed for boot anyway? Doesn't seem to be a power line issue and nothing is shorted or damaged etc. Anyone got any ideas of what I should try next?? Thanks
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