BMW U-Series BDC3 smart keys are extremely difficult to disassemble. Extra caution must be taken when copying these BDC3 keys.
Solderless clips only work for G-Series BDC3 models; soldering is mandatory for U-Series.
KEYDIY offers keys compatible with the U-Series- KD FGB57.
How to Disassemble BMW U Chassis BDC3 Smart Key?
Step 1: Disassemble the Key Shell
Remove the silver side trim.
Take out the mechanical key.
Remove the battery tray.
Step 2: Disassemble the Mainboard
First, remove the lower shell.
Use a screwdriver to push the clips on the upper cover, then remove the car emblem and side buttons.
Step 3: Take out the Circuit Board
Use a blade to cut through the ultrasonic welding seam.
Carefully cut along the ultrasonic welding line.
Pry open the clips.
The key circuit board can now be removed.
