If the object doesn't play mobile phone, zenly will show that there is no signal. If the phone is turned on, there will be.

The solution to no signal is as follows: back up the file and try to double clear it.

1. When the phone is turned off, press the power-on key+volume-up key at the same time (some phones press the volume-down key) until the phone is turned on.

2. The following options appear: rebootsystemnow: restart system wide data/factory reset: clear data/set factory mode. The volume key is the cursor selection key, which can be used to move the cursor, and the power key is the confirmation key.

3. Select wipedata/factoryreset, confirm, and then select yes to confirm. Phone numbers, text messages and applications that you didn't attach will be cleaned up. Then go back to the previous level and select rebootsystemnow for confirmation.

4. Wait a few minutes until the phone is turned on normally.

Methods to improve cell phone signal:

1, to solve the problem of poor signal, we must first determine whether the mobile phone signal is strong or weak! Under normal circumstances, the signal is between -40dBm and -90dBm, and the call will not be disconnected; The signal is between -90dBm and-100dBm, and the call may be dropped; After-100dBm, the call must be dropped. [Hide] Enter the interface about the mobile phone set by the mobile phone, click the status and information of the interface, and then click the network to clearly see the signal strength.

2. Signal reception is nothing more than 4G/3G/2G. Although 4G has been popularized now, it does not mean that the 4G signal in every place is the strongest, so we should choose the appropriate signal source according to different situations and switch the 3G, 2G or 4G signals of mobile phones. We can decide which signal is better by looking at the signal above! Go to more settings of your phone, and then select the network mode in your mobile network.

3. The mobile version of P9 can't use the above method, because it seems that mobile operators are not allowed to have 3G options (silently ~ ~), but it doesn't bother me at all. We enter the mobile network setup interface, and then enter the access point name (APN).

4. Then modify the name of the access point, and set the name as cmtds and APN as CMTDS. Pay attention to case, select Save, and then select APN as CMTDS. Mainly because most people choose CMNET and CMWAP, and seldom use CMTDS. Relatively speaking, CMTDS is more stable, which can keep the network speed in a stable state. This tutorial can effectively solve the problem that the mobile phone suddenly slows down when surfing the Internet in a crowded place, because there are too many mobile communication ports around, and switching ports back and forth leads to signal congestion.

5. Every new version is an optimization of the previous version, so the system upgrade is still very important.