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hi , i am trying to fix a dead iphone 6 . it heats up when powered on i know where the short is . when i remove the conductor the short is gone and when putted back the short comes back i also tried with new conductor but still the same any idea please help ??
can you see it now ?
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Rep: 14,9 mil
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It looks like you are referring to PP1V2_SDRAM?
PP_Buck4_LX is on one side of the coil going to PMIC, the other side is PP1V2_SDRAM, If you change L1217 and the short goes away, and then you put back a new Coil and it comes back...have you tested PP1V2 with the coil off? If SDRAM is not shorted when you pull it I believe the short would be under PMIC.
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Rep: 47
3
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yes i am sorry that i was not at home to get the exact information and part names but yes that is where i see the short and i removed the coil the short was gone and replaced the coil with new one and short came back i also tried to give direct current to one of those caps going to coil and it started heating up the COIL it self.
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Was there a short on the SDRAM side after removing Coil? If not, then I am pretty sure it is under PMIC but hopefully another tech ( @refectio ) can confirm before taking it off. I am fairly new and make mistakes too, but it is what it looks like to me. Just make sure to get a second opinion before removing or replacing PMIC as it sits right under CPU as well and wouldn't want to feel responsible if I were not correct
the short was gone from that line i didnt see any short but it came back right after i installed the coil.
It looks like pads G20 and G21 on PMIC are ground right above the pads F20 and F21 that are PP_BUCK4_LX, (One side of your coil)...and all of those pads on PMIC are directly opposite of where you were working. It may have been a bad coil and indirectly got a bit hot to cause a bridge there :(
do i have to remove the PMIC chip and replace with new ?
Jamil, when you remove the inductor, you need to test both pads to understand where the short is. PP1V2_SDRAM is not configured like PP_CPU so removing the inductor does not cleanly separate the PMIC from the downstream components.
With L1217 removed, if you see a short on the pin 1 side of the coil (look at page 13 of the schematic) then the PMIC's buck converter is shorted. If the short is on pin 2, then the short could be in the PMIC or the SDRAM or the RCAM circuit (look at L2330) or any capacitor on the PP1V2_SDRAM or the PP1V2_RCAM_CONN line.
@teetopp01
Iphone 6 same problem cames pp 1v2 shot sd ram any solution sir
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4 comentários
I have marked with yellow this area where i see shorted and the coil or inductor which heats up .
por Jamil Yousafi
I am looking for a picture but don't see one
por The Microsoldering Shop
did you get the pic ?
por Jamil Yousafi
I updated answer with ZXW Drawing of what I believe you are referring to...Double check SDRAM with out coil...just be careful! You are right next to CPU
por The Microsoldering Shop