iPhone 6 & 6Plus stuck Searching or No service (Error-1) fix
We have found the issue to be related to the Qualcomm Baseband PM8019. Typically the no service issue will present itself because of cracked solder joints under the ball grid array (BGA) and/or a faulty chip.
The issue with the no service problem is that you cannot simply replace the Intergrate Chip with another one because it is married to the central processing unit (CPU) and the Touch ID controller. [Not to be confused with the Touch IC controller]
One way to test and see if your device may have a service issue is to check to see that the phone is able to display the International mobile equipment identifier (IMEI) you can do this by going to the phone dialer and typing *#06# If the phone fails to display the IMEI number this may be a sign that the baseband is suspect.
With this “limitation” we are forced to use what we have in order to proceed further with the repair process.
The repair to restore service on the iPhone involves removing the motherboard from the phone and then also removing the EMI shield above the cellular components to expose the baseband.
There are couple of ics which manages your iPhone connection to the carrier. Out of these all iPhone network ic ( internal circuit ) most important is baseband ic MDM9625M OBA baseband CPU ic 4G LTE chip modem processor U-BB-RF.
iPhone 6 no service or searching solution of repairing baseband ic is very skilled repair. Remove baseband ic then clean the pads on logic board recall it and then install is again.
Once the chip has been reBalled and Installed, you can then clean the remaining flux with isopropyl alcohol. Then simply re-assemble the motherboard into the housing of the phone and test the service with an active sim card.