LG K40S Back Panel Replacement
This guide is designed for replacing the back panel of your LG K40S. It also serves as a supplementary resource if you need to replace either the fingerprint scanner or its corresponding flex cable.
Step 1 | Precautions
Press and hold the power key, select "Power Off" from the menu, and confirm.
The battery level must be below 25% before disassembling to prevent a potential fire hazard.
Step 2 | Removing SIM & SD Card trays
Insert a SIM Eject tool into the small hole on either side of the phone.
- Eject the 2 SIM and SD Card trays.
- Allow them to extend before removing from the phone.
Step 3 | Removing back panel
Locate the plastic back panel, which has a lower risk of breakage compared to glass.
- Use plastic picks to unclip the plastic clips holding the back panel in place.
- Exercise caution when handling the buttons on the back panel, as they are separate from their respective flex cables. Be mindful not to damage these cables.
Do not immediately remove the back panel completely — this may cause damage to the fingerprint scanner's flex cable.
Step 4 | Disconnecting fingerprint scanner
- Remove the back panel on the right side, referencing image 1.
- Use a plastic pick or spudger to disconnect the fingerprint scanner flex cable.
- Pull the old back panel away from the phone.
Step 5 | Removing fingerprint scanner from old back panel
- If also replacing fingerprint scanner, skip this step.
- Remove black tape covering fingerprint scanner using fingers or plastic pick, avoiding deep insertion if using a pick.
- Pull fingerprint scanner through old back panel carefully.
- Pull fingerprint sensor away from old back panel.
Use plastic pick to unadhere flex cable from old back panel, taking care not to damage it.