Remote control detection by the vehicle can among others be malfunctioning under the following circumstances:
Replace the battery
Do not transport the remote control together with metal objects or electronic devices.
In the case of a malfunction, unlock and lock the vehicle using the buttons of the remote control or using the integrated key.
BMW X3 Service & Repair Manual > Stabilizer bar: Replacing both rubber mounts for anti-roll bar mounting
Necessary preliminary work:
Remove REAR WHEELS .
Release screws (1).
Pull off retaining bracket (2), open rubber mount (3) at slot and remove.
Installation note:
Keep retaining bracket (2), rubber mount (3) and anti-roll bar clean and free from oil and grease.
Clean rear anti-roll bar ...