Hi guys ! Hope you are having a lovely day. This macbook pro came to the shop not powering on. Board is 820 - 00138. Its a macbook pro 2017 15". After disconnecting everything from the board and puting it on a charger i got 25-30mA. Right when i connect the charger i hear a click on the board. when i disconnect the cable i need to wait like for 5-10sec so the click happens again.If i put it back right away no click can be heard. I thought there may be a short somewhere but i cannot find it. so i checked power rails from the schematic. All the S5 rails were there. I think when i cleaned the area around clock generating circuit the board started pulling more current. When i plug it in its taking more like 30mA but it jumps every like 5sec to 200-250mA current draw. When it does all of the power rails pulse. Even PPVCC_S0_CPU is at 1,7V. So i thought okay it looks like a bad bios chip. I pulled it off. The chip was - 25Q64FVSIG . without the bios chip the board jumped to around 200mA and stayed. All the powerrails with the voltage they are supposed to. After trying to read the chip i got a full FF file. The chip was dead. I replaced it with a different chip MX25L1006E whitch is a 64Mbit chip too. and i am back at the pulsing and current draw 30mA to 200mA. This is my first post so if you see any mistakes please comment it i will improve. Thanks in advance have a nice day
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