overshoot
Member
Hi,
Customer brought a machine that started to have issues with the Touchbar.
He told me that it would not light up but if you press on it it would do the action.
He didn't bother and carried on using the Mac.
Then one day the Mac started to act up with the screen shutting off, touchbar too, even thought you could see the laptop was on.
It would sometimes work, sometimes not.
My tests:
I can confirm that sometimes I am getting a picture and the touchbar to work just fine.
Once I turn off the Mac, I won't be able to turn it back with the power button.
Sometimes, the Mac will turn on with no screen detected but external will work fine (as if you would close the lid)
So I thought it could be a hall sensor issue and did investigate that but my measurements were fine.
I re-did the solder joint on both sensor and it seemed to work for a while and then I wouldn't be able to turn the machine back on with the power button.
Checking the diode mode measurements on J4900 (Power button) and J4401, J4402, it seems that all the readings going to U3900 are off slightly.
There is minor corrosion on the edge of the board (left and right) but nothing crazy which I did clean and rework in some areas with no improvement.
I believe U3900 went bad but I can'ttell if I am right.
What else could I check before going the rabbit hole route and replacing U3900?
Can the hall sensor would mess up with the power button for example? (thinking the lid is down so it is disabled)
Is that going to be nightmare to replace U3900? Underfilled and bigger than the CD3215 chips.
I guess I know the answer for my 2nd question... ;-)
Customer brought a machine that started to have issues with the Touchbar.
He told me that it would not light up but if you press on it it would do the action.
He didn't bother and carried on using the Mac.
Then one day the Mac started to act up with the screen shutting off, touchbar too, even thought you could see the laptop was on.
It would sometimes work, sometimes not.
My tests:
I can confirm that sometimes I am getting a picture and the touchbar to work just fine.
Once I turn off the Mac, I won't be able to turn it back with the power button.
Sometimes, the Mac will turn on with no screen detected but external will work fine (as if you would close the lid)
So I thought it could be a hall sensor issue and did investigate that but my measurements were fine.
I re-did the solder joint on both sensor and it seemed to work for a while and then I wouldn't be able to turn the machine back on with the power button.
Checking the diode mode measurements on J4900 (Power button) and J4401, J4402, it seems that all the readings going to U3900 are off slightly.
There is minor corrosion on the edge of the board (left and right) but nothing crazy which I did clean and rework in some areas with no improvement.
I believe U3900 went bad but I can'ttell if I am right.
What else could I check before going the rabbit hole route and replacing U3900?
Can the hall sensor would mess up with the power button for example? (thinking the lid is down so it is disabled)
Is that going to be nightmare to replace U3900? Underfilled and bigger than the CD3215 chips.
I guess I know the answer for my 2nd question... ;-)