update - tried everything possible related to software - update, safe boot etc... and still seem like wifi is only working out of OS and not in OS regardless of the version..
could the problem be the low resistance on both these rails - [B]PP3V3_G3S_X[/B] and PP3V3_GS3_WLAN ?
if yes, would love for an idea on how to diagnose it and find the cause..
thanks..update - tried everything possible related to software - update, safe boot etc... and still seem like wifi is only working out of OS and not in OS regardless of the version..
could the problem
shlomim412
Member
Last Activity: Yesterday, 05:04 PM
Joined: 05-26-2018
Location: tel aviv
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can you please say what connects between these two lines?
[B]PP3V3_G3S_X[/B] and PP3V3_GS3_WLAN ?
when i inject to [B]PP3V3_G3S_X[/B] i see the voltage also on the other line.
r5530 seem to be missing... also missing on other boards from the same model as well.
thank you mon!can you please say what connects between these two lines?
[B]PP3V3_G3S_X[/B] and PP3V3_GS3_WLAN ?
when i inject to [B]PP3V3_G3S_X[/B] i see the voltage also on the other line.
r5530 seem to be missing... also missing on other boards from the sameLeave a comment:
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hi
RRAM and SMC reset didn't work. already tried..
the load switch put out 3.3v constant on both these lines, so looks to be enabled..
the wifi only works before the OS is loading... on the black screen with earth logo
for example, before recovery, or before diagnostic screen..
in the OS it detects the networks, but won't connect keep saying - connection failed
Leave a comment:
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you are absolutely right, so it's either i was readng the meter wrong or something changed after voltage injection.
now i was reading 52ohm on [B]PP3V3_G3S_X[/B] and PP3V3_GS3_WLAN
so i ended up soldering "new" U8215 from donor board (which was getting extremely hot at the beginning when nothing worked)
now getting 3.3v on both rails
now, it looks like a tough nut to crack because now WIFI WORKS before recovery screen (on black screen with earth logo),
but not in the recovery itself... i ended up installing with LAN cable which...Leave a comment:
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i injected 1v to [B]PP3V3_G3S_X[/B] and it only draws 0.02amp
nothing seem to get warm... got it up to 1.5v around 0.04amp draw.. nothing seem to get hot...
could be bad U3730 at this point?i injected 1v to [B]PP3V3_G3S_X[/B] and it only draws 0.02amp
nothing seem to get warm... got it up to 1.5v around 0.04amp draw.. nothing seem to get hot...
could be bad U3730 at this point?i injected 1v to [B]PP3V3_G3S_X[/B] and it only draws 0.02amp
nothing seem to get warm... got it up to 1.5v around 0.04amp draw.. nothing seem to getLeave a comment:
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hi
yes i do have power supply for injection...
you mean voltage to ground on
[B]PPBUS_G3H
PP1V8_G3S
PP5V_G3S[/B]
with usb c power connected?
i think i would have to put back U8215 for it to go to 20v again...
resistance to ground on [B]PP3V3_G3S_X[/B] is around 1.9ohm.hi
yes i do have power supply for injection...
you mean voltage to ground on
[B]PPBUS_G3H
PP1V8_G3S
PP5V_G3S[/B]
with usb c power connected?
i think i would have to put back U8215 for it to goLeave a comment:
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hi
"still same short, now with usb cable connected this specific area is not getting warm anymore.."
by that i mean - after i pulled out of the board U8215 - this area is no longer getting warm..
also all pins under U8215 seems to be ok and not shorted other than PP3V3_G3S_X ofcourse..
pulled out U8215 hoping it might be the cause of the short... but with it out of circuit PP3V3_G3S_X is still shorted...Leave a comment:
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Macbook a2141 - logicboard 820-01700 no wifi\bt
Hello
working on a2141 macbook, board number 820-01700 which has no wifi\bt and also no connection with LAN cable.
initial visual inspection the board looks good no visible corrosion or damage.
i found that PP3V3_G3S_X is shorted to ground (around 1.5ohm short)
and also PP3V3_GS3_WLAN i shorted to ground (same ohm reading, around 1.5ohm).
the board is working but no WIFI\BT as i mentioned.
with the usb c cable connected for measurement i noticed U8215 i getting EXTREMELY HOT
so i pulled it out figuring it might be causing the... -
did you manage to sort this out? could be a bad wifi connection?
worth to try with ethernet cable connected...Leave a comment:
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meaning? no longer available?
i was able to get version 1.0.2 is that the correct one?...Leave a comment:
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Hello
where is possible to get the minaT2 activator to unlock? or the tool to read the previous owner deails?
thank you!Leave a comment:
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with the fuse removed isl side should be more than 12.3v? i will check that again.. (t2 in on isl side, and not system side?)
i think ssd is fine since i can't find short in this area (on 2.5v rail for example)
i will measure u9580 and post...
i have another machine to try dfu... you suggest to put the fuses back and try DFU?
thank you!Leave a comment:
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hi
i'ts 3.6ohm between PPVCC_S0_CPU and ground
and around 37ohm and climbing to 150\200\300+ohm between PPVCC_S0_CPU and ppbus downstream pad. (with fuse removed ofcourse)...
is it correct? or too low readings?Leave a comment:
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hi
without the fuse it seems like ppbus on the producer side is fine - around 12.3v steady.
the inductors on these board are the ones that above the cpu\gpu? or others around the fuses?Leave a comment:
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a thermal camera can be useful in a case like this?
is it risky to inject more voltage and maybe than the fault component will be more obvious?
resistance to ground on the system side without the fuse and power is 60ohm and climbing...Leave a comment:
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hi
bumping up an old thread, sorry about that
no short on 2.5v ssd rail
i injected voltage to ppbus with the fuses off the board
it went up to 3v and around 2.5 amps draw..
the only thing i noticed is the ram on the back is getting hot
took out the plastic cover but seem like the whole area is getting warm but couldnt figure out what causing it...
any ideas where to check? what can cause ppbus to short ?
sadly i do not have a thermal camera......Leave a comment:
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Re: Macbook Pro a2141 820-01700 - short on PPBUS
hi
i injected 1v to the ppbus and is not showing on the cpu_s0 rail...Leave a comment:
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Re: Macbook Pro a2141 820-01700 - short on PPBUS
is that considered normal? it should be low resistance, right?...Leave a comment:
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Re: Macbook Pro a2141 820-01700 - short on PPBUS
resistance to ground is 3.3ohm on PPVCC_S0_CPULeave a comment:
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Re: Macbook Pro a2141 820-01700 - short on PPBUS
hi
i measured between PPBUS_G3H (shorted pin of the circuit) and PPVCC_S0_CPU and is around 133ohm.Leave a comment:
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