Chosen Solution
Hye I got an IPhone 6s for No Service issue. When dial *#06# showing perfect IMEI Number, also the setting showing IMEI and Modem Firmware Version. No Water Damaged history on this board. I do a little diagnose around the U_WTR_RF showing good measurement (PP_1v0_LD09). I never see people are talking about this issue on the internet. Seems like this case are very rare. Some people said I need to change the U_WTR_RF and some said U_BB_RF. How do I know which one should I start first ?
You can’t change the baseband IC (U_BB_RF) as it is code locked to the CPU and NAND although you could reball it. This problem doesn’t occur as much as the “searching” issue on the iPhone 6 and what we’ll typically see is an issue with the WTR or BBPMU. In the end, there is no firm solution to this and you will have to try things and see what happens and how durable the repair is. That’s how the iPhone 6 “Searching” problem first started. Techs noticed and applied fixes, with relatively low success rates. Some abandoned those repairs while other persisted. Eventually, a better solution was found however it doesn’t have a 100% success rate like the Touch Disease (6P) or Audio IC (7). That’s how this community progresses, through trial and error and sharing of our results. Apple certainly isn’t doing anything to help us.
