With hex screwdriver or bundled hex key remove two tip retention screws. Pull the tip out.

Remove grounding screw.

With prying tool carefully open the soldering iron handle casing, starting from tip socket side. Try to avoid breaking the holding pins near display edges at both casing sides.

Carefully pull out the small controller chip board near power and MicroUSB sockets.

At this step is recommended to put clear sticky tape over black button heads at casing face side. It will help to keep them in place during main board board removing and installing.

With Philips #00 screwdriver remove two contact clamps at tip socket side.

With a help of prying tool carefully pull out the main circuit board, starting from tip socket side.

During main board removing do not lose the grounding ring and two small black plastic button heads at casing face side.