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Will do diode mode, happen to have a good board here to compare. Is really U5701 a sissy? I pulled it off and back like 3 times already...

I measured current draw with my power supply at PP3V3_S4_PSOC and it was 0.0024 amps. So no short on this line. Then I bridged it which bring keyboard back to live. But still no trackpad, which I swapped with a known good and still no dice. 3.3v arriving at keyboard connector. Safe to say it's...

Both pins on Q7810 measured 3,33v. Can we assume is the board inner connection that got burned? I'm just about to bridge it.

Still not figured whats pulling this voltage down.

With U5701: Q7812 pin 2: 3.33v Q7810 pin 3: 0v U5701 PP3V3_S4_PSOC probe point: Voltage all around and never above 2.1v.

Removed becouse it was still measuring low. Measured resistance from SMC_S4_WAKESRC_EN to P3V3_S4_EN on C5701 and get 10k. Maybe another trace got burn? It feels like the schematics are incomplete on this one...

Measuring 3.17v at C5701 with U5701 pulled off.

After bridging I got 2,8v at the cap before U5701. Then removed U5701 and got 3,17v. Is that enough?

Measuring resistance between SMC pin 10 probe point and U9480 I get something in the order of mega ohm. Concluded that the board trace got fucked, making a bridge between those 2 points then.

Confirmed. Measured below 3.3v on SMC_S4_WAKESRC_EN too. As it is created by the SMC, can I assume it's a bad SMC case? If that is correct, woudn't be easier to make a bridge?

R7916 is not on the board. This schematic is clearly missing something. You think is ok to bridge R7916? May a board internal trace got burned and developed resistance, as PP3V3_S4 arrives with 2.4v at the keyboard and trackpad HUB?

PP3V3_S4 is arriving with only 2.4v at R5704, right before U5701. Pulled off U5701, all caps, U5750, U5755 but still no getting 3.3v. PM_SLP_S5L is measuring 3.3v but I think what is biting me here is that I only have boardview for revision A of this board. P3V3_S4_EN is not present but i don't...

Confirmed. Pulled off U7310 and it worked again same way as before (turn on then off after some time). One phase of the CPU got fried. Destination: Trashbin.

Don't think so. If anything, this board doesn't get vCore at all. After the last VCC regulator swap it stopped working, Will give it a last try as the inductor has nothing to do with the 5v rail that power the CPU.

Ater I swapped all 3 phases of the CPU VCC regulators, it won't turn on. I noticed that the inductor L7130, which is for the battery charger gets hot when ac connected. Can I blame a bad CPU yet and discard this repair?

Just swapped a cap and a resistor by mistake. Very hard to solder 0201 components without microscope. Will fix and get back here. It will be the first time with the replaced U7200. But that error made me have sure that is the U7200 circuit or some cpu feedback that is making it turn off.

Replaced U7200 (CPU VR12.5 VCC Regulator IC) and caps C7210, C7211 and C7212. After that, system doesn't power off but I get no vCore. CPU cold as a corpse...

Forgot to mention that after found abnormal 5v behaviour replaced 5.5/3/3v supply but still no dice. Something ahead of it is causing the problems.

Will mos def check all that again. Just reminding that this board doesn't have the boardview and i'm using one from a similar board. Will post here as soon as proceed with further testing. Thanks for the input!

Guys really need someone to shed a light on this...