Damage free disassembly of an BSD33 EU Smart Plug

How to open a CN39 type case for BSD33 EU smart plugs without damaging it.

This has become a commonly used case mould for EU and FR smart plugs and can be found under various brand names and model numbers (such as: BSD33). In these days of locked Tuya firmware the only option to flash them is by gaining serial access to the Wi-Fi module and to do that you need to open it. What is nice about this model is that it made out of two parts which aren’t heavily glued or fused together.

The example was done on an Athom plug.

Disassembly

Grab some adjustable pliers and wrap them with duct tape or electrical tape to avoid damaging the plug surface.

Adjust them to the width of the plug, grab the top as pictured. Slowly apply pressure while trying to pull it out until it pops out of the case. If it doesn’t budge use a rubber mallet to lightly tap around the plug and loosen it up.

Move pliers closer to the button side and repeat the process while jiggling the plug until the top part comes off.

Unscrew the PCB from the case and push it out by tapping or applying pressure on the AC prongs on the outside.

Flash away!