820-01987 20v 0.019A pp3v3s5 pulsing

posarah

Member
12.27V @ C7050 with F7000 removed. That's only if i use the port towards the screen side (slave port). If I use the port towards the battery side (master) I get 0V. That ports not working at all stays at 5v 0A no matter what you do. Nothing is shorted though. Checked D3399, D3300, D3301 and F3000 and neither seem to be getting any voltage. Checked diode mode on them and the readings match open board data. 3v3 RTC wont come up using the master port either, only works with the slave port.
 
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posarah

Member
May have found a problem. PP3V3_UPC_XB_LDO seems to be a bit high, 3.48V instead of 3.3. Diode mode is .471 when open board data says it should be .515.
 
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2informaticos

Administrator
Staff member
Check/compare diode mode readings between both ports.
Pay atention to CC1/2 lines.
S-UEM2 tool is helpful in this case.
 

posarah

Member
CC lines are all 0.577 diode mode to ground. Checked at their respective capacitors near their respective CD3217s as it is impossible to get to the protection diodes as I have the shield on the USB C charge port on so it covers them. Still going through and comparing the rest of the lines.
 

posarah

Member
Interesting after poking around a bit checking the other lines it seems that the CC lines have dropped slightly. Now there reading .569
 

posarah

Member
Ok finished checking all the lines I could get to. Some only go to components under the thunderbolt shield which I haven't removed and would rather not for now so I didn't check them.

USBC_XB_CC1 @ C3213 = .569
USBC_XB_CC 2 @ C3214 = .569
USBC_XA_CC1 @ C3113 = .577
USBC_XA_CC2 @ c3114 = .577
PP20V_USBC_XB_VBUS @ D3398 = .136
PP20V_USBC_XA_VBUS @ D3399 = .142
USBC_XA_SBU2 @ test point = .635
USBC_XB_SBU2 @ test point = .631
USBC_XB_SBU1 @ test point = .632
USBC_XA_SBU1 @ test point = .630
TP_USBC_PP20V_XB @ test point = .131 Trackpad disconnected (assuming that's what TP stands for).
TP_USBC_PP20V_XA @ test point = .138 Trackpad disconnected (assuming that's what TP stands for).
 

posarah

Member
Only CD3217s I have are from that A2159 820-1598 are they compatible with this board? They do match the markings, both say CD3217 B12 only the second line differs does that matter? I always thought the second line was just a serial number / batch or DOM info but wanted to double check. Need to get a stencil as well only got one for the 15s.
 

posarah

Member
I've ordered some replacement ICs and stencils as I didn't have a matching stencil. I was hoping the iphone ones would suffice but no such luck.
 
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