Chosen Solution
Hi all, I bought an iPhone 7 that came with no power, no charging issue, and without water damage. The phone was never opened and the board looks brand new. So I decided to look for the problem. After going with troubleshooting , and after pressing the power button, the phone was drawing around 0.6 Amps, but no shorts were found in all VCC lines (MAIN, BOOST, etc). In fact all the PP lines were with the right voltage values. Because there was some small heating coming from the CPU side (I couldn’t verify which side -bottom or top- was heating first), I decided to remove the stickers. After that, I could’t find any damage or short, so I removed the CPU shield (same as I did before). Then, I checked all voltages and looked for a short on VCC lines, but everything seamed normal. However………. the current draw is now around 0.03 Amps after removing the shield. Any clue? I am afraid that I had a damaged/broken CPU chip (maybe caused from a faulty charger?, which I cannot know because the phone wasn’t mine). Did the heating (from removing the shield) revealed the real problem? Or is it just something else? Does anyone has faced this problem before? Thanks in advance for any hints! Regards.
What do you mean by “all the PP lines”? There are nearly 50 power lines in an iPhone 7…have you tested them all or just a few. As for the “VCC” lines, there are only two. Please be more specific about which lines you have checked and whether or not they were looked at in diode mode, voltage mode etc. The better the info you provide, the better the answers you will receive. Working on dead iPhones requires a systematic approach when there are no obvious failures. You start with the three main lines, then Boost, then the main BL/LCM/Touch lines, then the PMIC outputs (switchers and LDO’s), then the BBPMU outputs and then whatever LDO’s you haven’t already looked at (Mesa, Mamba, Camera etc.). If you have any visible clues, like corrosion, burn marks or heat signatures, then you can focus on those first.
Remove nand then check itunes detect or not
same problem.any updates mate?
No. Unfortunately that was just garbage.
