Fix Your Stuff Community Store

Repair information and guides for the iPhone 6S released by Apple on September 25, 2015. Models: A1688, A1633

2687 Questions View all

Options

iPhone 6s short on PP_1V0_SMPS3 , do I inject 1 volt on this line

Hi all , , i've got an iphone 6s here which i was told had been water damaged , having taken it apart it has obviously had a repair attempted already as the shields were off and under fill dug away , the board looks relatively clean with no signs of corrosion there are however some components missing , i think whoever took the under fill off was a bit heavy handed , as FL3202-1 was missing , i believe this is a filter on the vcc main to camera .. am i right in thinking the phone should still boot without this ?

The phone will not boot nor is it seen by itunes

I have checked voltages around tristar , PP_VCC_MAIN is present, so is PP3V0_TRISTAR . and PP1V8 and PP5V0_USB , I replaced tristar to rule it out , still no change

My bench ps reads 15 ma draw which changes to 27 Ma when prompted to boot .. charger current reads 43 ma .

Nothing seemed to be getting warm on the board so i started checking randomly for shorted components , i found line PP_1V0_SMPS3 is shorted to ground , from what i can see there are only 3 components on this line and points under U_BB_RF ,

should i inject 1 v from my ps into this line to see what gets hot ?

Answered! View the answer I have this problem too

Is this a good question?

Yes No
Score 2
Add a comment

2 Answers

Filter by:
Most Helpful Newest Oldest
Chosen Solution

Options

The phone should boot with the missing filter.

As for the short, there is also a bank of 8 caps to filter this line, check page 40 of the schematics. I would also check the other outputs of the U_PMU_RF (the RF version of the PMIC). The short could cause the PMU_RF into current limiting and then causing other issues with BB and the rest of the RF circuits. That might be why the phone does not boot.

It appears there is more damage than what you would expect based on the visuals. I would probe the PMIC and PMU_RF to see if there is anything else. You could also inject voltage.

Was this answer helpful?

Yes No
Score 4

8 Comments:

Hi , some spare time at last .. ahh yes i see the rest of those caps now , not sure what i did but i do have zxw ,

the PP_0V9_SMPS1

PP_1V225_SMPS2

PP_1V0_SMPS3

PP_1V85_SMPS4

PP_1V0_SMPS5

and the whole row of lines from the right hand side of the chip on the schematic are 0 volts , all the PP_VCC_MAIN in seems to be there for that chip but no other volts in , i do however have 1.8 v on pin 74 AVDD_BYP ,

so the chip has PP_VCC_MAIN , and does one of the smaller voltages turn the chip on ?

by

thanks , i will order a new one , so if i remove that chip the short should go ?

by

There's only one way to find out...;>)

by

got that chip off but still have short , i have connected my ps at 1 v to the + side of C3611_RF i cant find anything getting warm even , i cant measure any voltage though at the connection too the board , its at 1 v when i take the - off but as soon as i connect it theres 0 .

I have tried lowering voltage on ps but still getting 0 ?

by

could this be my power supply , as in the instructions it says "the power supply is not designed to operate in constant current mode as a current source ?

by

Show 3 more comments

Add a comment

Options

I see the question marked answered, but the outcome of the issue is not explained?

Did you manage to get the phone to boot OP? I have the same issue

Was this answer helpful?

Yes No
Score 0
Add a comment

Add your answer

markparnell1972 will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 3

Past 30 Days: 5

All Time: 1,237