A1278/820-2936-B/ Turn on the cooler at maximum, it’s too slow!

[gabrielnote]

One more for you! Plate is in great condition without any sign of oxidation! I’ve tested another keyboard and nothing, and now I don’t know what else I can do! I know the problem has to do with sensors, but I don’t know what to analyze in this case. I await instructions, thank you!

 

[2informaticos]

Try first disconnecting webcam cable.
Also test with known good trackpad; its flex can cause problems.

 

[gabrielnote]

Procedures performed and continued the
problem. Can you tell me how to use Apple Service Diagnostic to get information about which area the problem is occurring?

 

[2informaticos]

ASD 3S144 is the version corresponding to your machine.
I'm sure you can find lot of info, even videos, searching with Googlr.
Good enough to run EFI version only.

ASD EFI 3S144.rar

drive.google.com

Just for test, remove first R5222/3 and check if symptom changes.
You can also test disconnecting BIL (J6955).

 

[gabrielnote]

One thing I noticed is that the felx of the TP is oxidized, replaces the same, but the symptom persists, the cooler is gradually rotating 0until it is 100% and very slow system!
I looked around the TP connector and found no oxidation. Another thing I noticed is that the battery does not charge, the LED does not turn orange and when I take out the charger the machine disarms for lack of charge in the battery. Could that be related to the problem?

 

[gabrielnote]

In the diagnostic test gave the following error: 4sns/1/C0000008 TPCD-124

 

[2informaticos]

You should test with known good trackpad flex/board.
TP board includes some thermal sensors.

No Magsafe light is not related.
You should check U6900/1 traces and try another DCIN board.

 

[gabrielnote]

I already put her plate in another case of another Macbook that I know to be working perfectly, so the question of TP is eleminada, the flat also put a good one.

I’ll try the other procedures!

 

[2informaticos]

"Just for test, remove first R5222/3 and check if symptom changes.
You can also test disconnecting BIL (J6955)."
Did that?

 

[gabrielnote]

I don’t understand why you put (/) at the end of the component, because that being only 1 resistance R5222
Would it be for me to remove the resistances r5222 and the r5223?

 

[2informaticos]

Exactly, there are two resistors; one for each I2C bus line.

 

[gabrielnote]

Removed the requested resistors. Also disconnected the J6955 and tested with another DCIN board and got the same symptom. Only the board on the workbench both with all its connected peripherals gets the same symptom.What do you think?Do we have anything else to do before then?

 

[2informaticos]

Then possibly SMC, or PCH problem...