Hi all, I am working on a MacBook Air A1466 820-00165-A. It turns on fine (3.3-5v-1.8V all good), there is a fan spin & the initial startup too, the fans spins stops & then spins again, but no display all. Upon checkup I noticed that U3900 chip Heats up, I measrued a short in this area, C3931 & C3933 shorted. Actually the chip was shorted, this is why the caps were showing 0 ohms. I replaced the chip with a new one but now the chip gets very hot. Is there any reason why is this chip getting hot & no display at all. Appreciate a reply. Thanks
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Re: MacBook Air A1466 820-00165-A U3900 Heats up
Hi I have the same A1466 in absolutely same condition. U3900 is not overheated and there is no shorts on caps near, but it has high temperature. Fan spins, all voltages are present, no image and backlight. Board has liquid damage on other side of cpu, I changed all components and checked all board for another damaged lines, but still no luck. Cpu temperature is very low, even when fan is off. I guess maybe cpu is dead -
Re: MacBook Air A1466 820-00165-A U3900 Heats up
found out that CPU_VCCSENSE_N is shorted to gndComment
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