If you have an iphone that doesn’t turn on and doesn’t draw any amps through the usb charging cable, then one of the first things that you should check is a short on PP_VCC_Main, which is the main power line for iphones. Here’s a picture:
In the ZXW Tools picture, you can test for a short on VCC_Main by flipping the logic board over (on an iphone 6) and put your multimeter in diode mode to test for continuity. Continuity testing is essentially testing to see if one point on a logic board is connected to another point via something metallic. If the two points are connected, then your multimeter usually beeps to signify continuity.
For a short, a beep is bad because it says that one of the components, like a capacitor or a resistor, is not doing it’s job correctly. It’s good for us repair technicians because it tells us that something is broken along that power line.
Here’s a short video of me finding a short to ground on PP_VCC_Main on an iphone 6 and resolving the problem through deductive reasoning.
Since there are so many components on the PP_VCC_Main power line, it’s not very efficient to test every component one by one. If you do that, then the time cost outweighs the cost of the repair, so you have to find ways to maximize efficiency, if you want to make money in this business.
Nice work. Question: do you do any reballing and if so what reballing or rework station do you use?
I’m opening a shop in the Cayman Islands in a few months and looking to buy some equipment
You can see all of the equipment that I use in the Tools and Equipment link above.
Nice job. I have a question. Is it the same way if the phone get shorted on pp_vcc_batt?
That’s a different line, so you will need to see what is connected on that line.
Nice job. I don’t have steady enough hands anymore or the equipment and materials for this. Do you offer mb repair services?
Hello Mike
Please tell me what is pp vcc main in words because i am very new in this 🙂
Thank you from Spain!
G.C
Hello. Do you know what causes iphone 6 PP0V95_fixed line to short? I have removed backlight sircuit and now I noticed that this PP0V95_fixed is shorted. This is second iPhone 6 when this line get shorted and I have used freeze spray to find shorted component but nothing gets heated up when put current to that line. Any ideas? Thanks
PP0v95 is a low resistance line. According to Ohm’s law, I=V/R and max current on this line is 3.3A, which means that it’s a low voltage, high current and low resistance line. R= V/I = .95V/3.3A = .28 ohms. Don’t assume that a shorted cap means that the circuit is shorted. There are lines that are supposed to be low resistance. PP0v95 is supposed to be low resistance.
Thank you for the answer and information Michael, I appreciate! Nice to learn new things 🙂
Can you say about iPhone 5c not charging (no charging bolt) and it draws 0.09-0.11 amps. I’ve already changed tristar two times and still the same about 0.10 amps. Board looks good tho :/
Thank you so much Mike for answer me !! Respect !!