Keep holding them until you see the Huawei logo and the EMUI update screen appears.
There are several reasons why you might need to flash your Huawei CUN-L21 device: huawei cun-l21 flash file sd card
It runs Android 5.1 Lollipop with Huawei's custom EMUI 3.1 Lite interface. Knowing this helps ensure you download the correct software version. There are other variants like the CUN-L01, so you must confirm you have a CUN-L21 before proceeding. Keep holding them until you see the Huawei
Insert the MicroSD card with the dload folder into the powered-on phone. Open the phone's native . Enter the following secret code: *#*#2846579#*#* A hidden Project Menu will instantly open on your screen. Select option 4. Software Upgrade . Select SDCard Upgrade and confirm your choice. huawei cun-l21 flash file sd card