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Original post by: Nick kus ,

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Ok guys, error -1 is an error where your baseband can't connect to the cpu. For those who don't know, there is a big brain (cpu) for the majority of the phone and a little brain (baseband cpu) just for the cell network.  Typically the problem is caused by a cracked solder joint somewhere due to a drop or jolt.  When you heat or cool anything on this earth, it changes in size ever so slightly. Heat expands the object and cooling shrinks it. So either way you go you are shifting the chip ever so slightly and the micro crack touches again and you get a working device. However once it returns to normal temp the crack will reappear. The most obvious spot to crack is under the baseband cpu or the big cpu. This is because the solder contacts are the smallest on the phone here and have very little yield strength to resist a jolt or drop.  If Apple didn't use underfill (a water proofing black tar) on the chips you could just throw it in a reflow oven to fix, but they do. The only correct fix therefore is to remove and reball the baseband cpu!  This is the hardest thing to do next to reballing the main cpu and only a handful of techs can accomplish it. If you do use the oven,  you will prob lose network eventually and the next restore will be a repeat.  If the baseband cpu went bad then you have to pull the trinity from a broken phone and put it on yours. If you don't know what that is, then you will never be able to do it anyways ;) If you are a tech and do decide to reball it, clean the tar around the contacts with a needle. The board contacts rip off easy because they are so small.

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