Bluetooth Speaker Repair

To start the repair, we need to disassemble the device and look at what we have inside:

Inside the device, there is a speaker with two backlit LEDs, a main circuit board, and an 18650 3.7V 850mAh Li-ion battery with an external protection circuit.

The next step is to clean the parts. Plastic parts are cleaned with a cleaning solution, and the main board is cleaned with an alcohol solution.

A visual inspection revealed that wires at the connection point with the loudspeaker had been deeply corroded, and one of the wires was broken.

Speaker wires were stripped and resoldered:

Additionally, the original white backlite LEDs were replaced with red and blue LEDs.

After powering the device using a wall charger, it appears to be working properly.

The original 18650 850mAh Li-ion battery was dead and needed a replacement.

For the replacement, I picked a 14500 3.7V 800mAh Xtar Li-ion battery with an internal protection circuit. The battery can be easily fitted into a holder for AA batteries.

2xAA battery holder was repurposed to hold one 14500 3.7V 800mAh Li-ion battery:

The battery can be easily replaced if needed.

The battery holder is glued to the internal wall of the speaker tube.

For the final step, I wrap the speaker tube with self-adhesive foil to give it a fresh new look: