Disassembly/Repair of the mobile device ZTE Nubia Z9 Mini (ZTE Nubia Z9 Mini NX511J) with each step description and the required set of tools.

Use the ejection tool (aka Needle) or Paperclip. Push the tip all the way into the hole until the tray ejects, and then pull the tray of SIM and Memory card (Micro SD) out.

⚠️️ Pay attention! The tool must be inserted into a hole on the edge of the phone's housing. Do not press too hard. It may break the tray eject mechanism.

Using a spudger or a plastic pick, carefully, around the edge, detach the back cover clips, and remove it.

Do not insert the tool deeply or bend it. Otherwise, the housing may be tampered with or damaged.

Using a screwdriver hex T5, unscrew 9 screws.

If the screws are different: ℹ️️ Be sure to note the location of the screws before disassembling. When assembling the device, screwing the screw in the wrong place may damage the device or its parts. To avoid damage, the removed screws and individual pieces (as gaskets or brackets) must be laid out in the appropriate order, or the screws and their holes in the phone must be marked with colored markers.

Pry over the edge and remove the cover hiding the battery.

Using a screwdriver hex T5, unscrew two screws.

Pry over the edge and remove the cover with a flashlight and camera lens protector.

Using a screwdriver hex T5, unscrew five screws.

Pry over the edges and remove the loudspeaker assembly.

Disconnect the battery connector as soon as possible. It is better to use a non-metal or plastic tool to avoid any damage.

ℹ️️ The ZTE Nubia Z9 Mini model has a battery Li3829T44P6hA74140 with 2900 mAh capacity (aka rechargeable battery).

⚠️️ It is highly recommended to disconnect the connector to avoid possible short circuits during disassembly.

⚠️️ Be careful! The battery is glued from the inside by the manufacturer.

⚠️️The cable of the side buttons is glued under the battery to the display frame.

To remove the battery we can use a plastic tool and isopropyl alcohol to soften the adhesive base.

Disconnect the connector on the motherboard, and remove the rear camera.

Using a screwdriver Phillips 1.5 mm PH #000, unscrew two screws securing the motherboard.

Disconnect the connectors of the coaxial cable, cable to the sub-board, display module cable, sensor cable. Also, we have to pry carefully up at the side to unstick the vibration motor.

⚠️️ Do not pull on the cable or pry it with a sharp tool, the connectors are pretty weak and break easily, or the cable falls out of the end (lug).

Carefully remove the printed circuit board. There is no need to use a lever or try to reach the circuit board by force. Make sure that nothing is getting in the way or holding the circuit board.

The motherboard, also, may be attached with attachments like latches or hooks, be careful.

⚠️️ Do not bend the circuit board when removing it or push tools under it. Unbeknownst to yourself, you can damage components or cables from the inside.

Disconnect the coaxial cable connector, cable to the mainboard.

⚠️️ Do not pull on the cable or pry it with a sharp tool, the connectors are pretty weak and break easily, or the cable falls out of the end (lug).

Using a screwdriver Phillips 1.5 mm PH# 000, unscrew two screws. Also, we have to remove the coaxial cable.

Remove the sub-board. It may be glued to the frame with metalized tape, so to facilitate the process, the sub-board can be heated a bit.

The sub-board, also, may be attached with attachments like latches or hooks, be careful.

ℹ️️ The sub-board contains a charging port (Micro-USB), an antenna unit.

⚠️️ It is not necessary to insert the tool underneath when removing the sub-board. Internal components could be damaged.

Carefully peel off the flat cable with a microphone and navigation buttons.

ℹ️️ In the display frame remained: the earpiece speaker, side buttons.