Released on September 19, 2014, this 4.7" screen iPhone is the smaller version of the iPhone 6 Plus.

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iPhone 6 water damage repair board

Hi every one!

The iPhone 6 dropped in a water and will not turn on anymore. I checked and removed the capacitor C5202_RF (smoked / shorted), removed the shields and cleared the board, but the phone still shorted.

The power supply show me 0.050A (50mA) when I connect only the board, but I can not get any component warmup. I tried to use the term paper to help me identify it, but I have no dark points to analyze it.

I checked some capacitors around the power controller, but it was a random test flowing the schematics diagram, but nothing in a short.

Any suggestions for next verification?

Thanks

Felipe

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Have you properly decontaminated the logic board in an ultrasonic bath? That is the first step that must be done.

As for troubleshooting a dead phone, you have to take an analytical approach. Different techs take different approaches but here is what I suggest. Start by checking PP_BATT_VCC & PP_VCC_MAIN for shorts. If one of those lines is shorted, you have to find the source. This is not always easy but look for visual clues such as where the board was aggressively attacked by corrosion. Your phone doesn't draw much current so you won't be able to look for heat. What this tells me is that some important subsystem is not working, impeding the startup process.

Look at the output voltages of the PMIC, such as PP_CPU, PP_GPU, the SDRAM and NAND outputs as well as the Tristar output. Look for shorts with the device unpowered and then check for voltages with the power applied. Report back!

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Hi Minho, thanks for the guide line...

Yes, I decontaminated the locig board using ultrasonic bath and 99.9% Isopropanol.

The PP_BATT, PP_VCC_MAIN and PP_CPU is OK, have no shorts.

The PP_GPU is in short, but I removed and tested all caps in this line ( C1203, C1227, C1210, C1226, C0442, C0466, C0445, C0448, C0419, C0420, C0475) and the shorts keeping in this line.

I suspect the U1202 is burned... My thinking is correct or do I need check any other line?

Thanks

PS: I'm new in this forum... the best way is to comment you answer or add a new answer? thanks again

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Commenting on the relavant answer is the proper way to do things. That way I receive a notification and it keeps the "discussion" properly sequenced.

PP_GPU is a low resistance line. Most meters will "beep" when measuring it but that doesn't mean it is short-circuited to ground. You need to see what the measured resistance is. On the iPhone 6, PP_GPU can measure anywhere from 20-60 Ohms. A true short is when the line has less than 1 Ohm.

Keep checking all the outputs of the PMIC.

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Hi,

The PP_GPU is 37.6 Ohms

I checked all of these outputs about PMIC (U1202):

Reference [test point] = voltage with power button released / pressed

PP_CPU [C1292] = 0.001/0.001

PP_GPU [C0442] = 0.001/0.001

PP_VAR_SOC [C0508] = 0.002/0.002

PP1V8_SDRAM [C1243] = 0.471/0.452

PP1V2_SDRAM [C0429] = 0.002/0.002

PP0V95_FIXED_SOC [C0435] = 0.002/0.002

PP3V0_NAND [C0634] = not stable

PP1V2_NAND_VDDI [C0601] = not stable

PP1V8 [0616] = 0.005/0.005

I just plugged power supply in battery connector (3.9V) and it show me 0.054A with and without power button pressed.

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The voltages I used 2V scale (continuous voltage) and resistance I used 200 Ohms scale. I had a old fashion multitester, but with a good precision.

I think the 1mV/2mV is a read error by the multitester, but I posted only to you know what I got here...

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Well most of those voltages are 0. You need to test those lines, unpowered, in resistance mode to see if they are shorted. If they aren't then the PMIC may be your problem.

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Felipe Kashiwagura will be eternally grateful.
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