When the BDC2 module in a BMW G-chassis vehicle is removed (typically for key programming or replacement by Yanhua ACDP2, Xhorse key tool plus etc), the wipers may activate continuously. This is a known issue that can drain the battery and potentially damage the wiper motor. Sometimes, the headlights may also turn on.
Solution
To resolve this issue, you need to remove the designated fuse to deactivate the wipers:
Identify the correct fuse: Consult your vehicle’s owner’s manual or a fuse diagram specific to your BMW model to find the exact fuse responsible for the windshield wipers.
Fuse box located on BDC2 unit.
Remove the corresponding fuse.
Remove the fuse: Carefully pull out the specified fuse from the fuse box while the BDC2 module is out of the car. This will cut power to the wipers and stop them from running.
After Installation
Once the new or programmed BDC2 module is successfully installed and all programming procedures are complete:
Reinstall the fuse: Put the designated fuse back into its original slot. This should restore normal wiper function.
If the problem persists after reinstalling the module and the fuse, it may indicate a wiring issue, a faulty connection in the wiper control module, or the need for a system recalibration or full software re-programming using a diagnostic tool. It is recommended to have a professional diagnose complex electrical issue.
