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[SOLVED]A1466 820-3437 Runs only if SMC bypass

Tony Tone

Tony Tone

Member
I've been working on this board for some time now. It was slightly water damaged and had no green light and was missing some rails.

I changed the SMC and have green light and all my power rails. CPU gets warm. Fan spins for 8 seconds, off for 4 seconds, and on for 4 seconds, and will turn back on and stay on.

U7200 was hit the worst. Had to make jumpers and changed the chip. C6950 & C6951 hit with blown vias. U5810 pin 10 corroded and switched with one from 820-00165 board. U5660 pins 4 & 5 have a little corrosion but left alone; seems ok.

I have tried a couple SMCs and get the same results.
 
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Tony Tone

Tony Tone

Member
No Title

16.7 on R7121 & R7122
8.57 on R7150-R7152
SMC_BC_OK = 3.3
 

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dukefawks

Administrator
Run ASD to check for sensor errors. Check if audio device is detected in OSX. All audio circuits are on the DC board, so replace that including the cable.
 
Tony Tone

Tony Tone

Member
No Title

Says SMC maybe the issue. I have put like 4 different SMCs on here the pads are starting to widen with the coated traces and probably combining together. Or may be the SMC itself. The area looks around it and have checked it dozens of times.
 

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Tony Tone

Tony Tone

Member
What is the correct ASD for Early 2014 13" Macbook air? Most lists do not have it listed, one on github lists 3S156 which most others list for 2013 only. Is the link posted accurate? Also having a hard time finding any newer than 156.

Downloaded ASD 3S156 found on an old thread here and it boots into ASD but a message pops up stating it is the wrong machine.

A1466 EMC 2632 Serial # C02L40LDF5V7

The readme only lists 2013.
 
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dukefawks

Administrator
The error you have now is most likely a bad trackpad cable/trackpad/connector. Inspect for corrosion

3S156 is the last ASD that would run on an Air so yours can only run AST2 which is not going to happen.
 
Tony Tone

Tony Tone

Member
Really?! No trackpad connected will cause high fan spin? I didn't know that ! Yes, problem solved!

QUESTION: So to refer back to current sensing, that takes place at R7120-R7122 correct? Or, there are more areas for current sensing? And anything connected to the SMC that has an issue can cause high fan spin as well, ie camera, battery, trackpad?
 
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dukefawks

Administrator
Anything connected to SMBUS can mess with temp. sensors and cause high fan spin. Without trackpad you will always have high fan on ANY macbook.
 
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