Chosen Solution
Charger connected when not show any screen, not reponse I checked rails PP3V0_S2R_TRISTAR : 0v PP1V8_S2R_TRISTAR : 0v PPVBUS_PROT : 4.4v Ppvbus e75 usb conn : 4.4v Help me please Sorry I cannot speak english well Update (03/07/2017)
I checked VCC MAIN VCC MAIN : ALL 5.2V, NOT SHORT and PP3V0_S2R_TRISTAR , PP1V8_S2R_TRISTAR line
checked but all capacitor not short, volatage is 0 upload several pictures, check please
The TRISTAR voltages should not read 0V. Those voltages are being driven by the PMIC (U8100). You will need to determine if the 0V, probably caused by a short somewhere along the line, is due to a faulty PMIC, faulty Tristar (U6000) or a bad capacitor along the line. UPDATE (2017-03-07) I saw your update on the measured voltages. It would appear that the LED Buck Converter is not doing its job. This is caused by either defective passive components, such as the coil and diode (these are easy to check), or it is a defective PMIC. Considering you have other voltage issues (i.e. Tristar), I would lean more towards the PMIC. However, given that the PMIC is much harder to replace, you could try changing Tristar first to see if that solves the problem. I would also probe all of the output voltages on the PMIC to see if there are more problems.
Are those going into or coming out of the tristar? Test for vccmain, and short to ground on those pins. Also will it power up with a known good battery?
solved ? this problem ipad air ?
