ytesfay80
Member
This board I received had liquid damage and after replacing some components and ultrasonicing the board it would power cycle, pm_slp_s4_l would pulse for one second on startup and there was no 5V_S3/0 voltages.
I had to search around for a long time and ended up seeing that L4605 and C4695 were not looking great so I replaced them and pm_slp_s4_l came back.
Pin 4 is now present on U7501 but there is no voltage on Pin 5(PGood)
I ended up seeing PM_SLP_S3_L was missing and when I went to R8178 I saw it was only hanging on to Pin 2 as if it was knocked away from Pin 1(not sure how that happened). I pulled R8178 completely off the board, plugged in the charger and measured Pin 1 where it showed 3.3v and Pin 2 was around 1.3v. I put another resistor on there and Pin 1 and 2 would both measure 0v and there was no short to ground in diode mode.
I removed R8178 again and measured and again the pad on Pin1 measured 3.3v and when I put another resistor on there it went back to 0v on both sides.
I replaced U8180 thinking that was the issue but still there is no voltage on R8178.
The resistance of R8178 is 100ohms.
Diode Mode of R8178 is around 0.47v and Pin 1 of U8180 is around 0.52v
I had to search around for a long time and ended up seeing that L4605 and C4695 were not looking great so I replaced them and pm_slp_s4_l came back.
Pin 4 is now present on U7501 but there is no voltage on Pin 5(PGood)
I ended up seeing PM_SLP_S3_L was missing and when I went to R8178 I saw it was only hanging on to Pin 2 as if it was knocked away from Pin 1(not sure how that happened). I pulled R8178 completely off the board, plugged in the charger and measured Pin 1 where it showed 3.3v and Pin 2 was around 1.3v. I put another resistor on there and Pin 1 and 2 would both measure 0v and there was no short to ground in diode mode.
I removed R8178 again and measured and again the pad on Pin1 measured 3.3v and when I put another resistor on there it went back to 0v on both sides.
I replaced U8180 thinking that was the issue but still there is no voltage on R8178.
The resistance of R8178 is 100ohms.
Diode Mode of R8178 is around 0.47v and Pin 1 of U8180 is around 0.52v
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