GF's iphone5s port version A1530 Unicom 4G is always unable to connect the problem, the root cause is that there is no 4G switch . The Hong Kong iphone only has a 3G switch. That is, when the 3G is turned on, the 4G signal is found, but only 3G and 2G are turned off. Let the phone signal stay on the 4G signal network. The 4G signal is now almost impossible to communicate. Although the phone has a signal, it will be in an unreachable state.
The 4G network currently does not support calls. When the "Enable 3G" switch is turned on, the 3G module of the phone and the 4G module are turned on simultaneously, so the 4G signal can be searched. When the "Enable 3G" is turned off, the 3G and 2G modules are turned off, but the 4G module does not, the phone still stuck in the 4G network state! And when there is a call, 4G must fall back to 3G to make the call, but the 3G module has been closed, unable to come down to the 3G signal, the lead telephone can not be entered, the prompt cannot connect. operators are 4G Internet access, call to switch to 3G or 2g.
The solution is to jailbreak or change the 3G card.
After jailbreak:
1, access to path/private/var/mobile/library/caches and select com.apple.MobileGestalt.plist for editing
2, change the MF354 to your phone color, capacity corresponding to the country line model
16GB Black: mf396ch/a
16GB White: mf397ch/a
16GB Gold: mf398ch/a
32GB Black: mf402ch/a
32GB White: mf403ch/a
32GB Gold: mf404ch/a
64GB Black: mf405ch/a
64GB White: mf406ch/a
64GB Gold: mf407ch/a
3, change the ZP to Ch
4, change zp/a to ch/a.
After the modification can be resolved because there is no 4G switch caused the network can not fall down the phone leak, the phone is not connected to the problem.
Solve the port version A1530 iOS8 unicom 4G phone can not be connected to the problem, unicom 4G switch Open method