Q: How do you access and replace the door latch assembly,Door Lock Cylinder and handles on BMW Z4?
A: The interior door handle is integral with the door trim and cannot be replaced separately. To access the front door latch assembly, fully open the window and raise it approximately 140 cm, then remove the door inner trim panel and carefully peel off the plastic sound insulation panel to access the latch components. Loosen the window clamp retaining bolts, tape or wedge the window into the closed position, and remove the nuts securing the window rear support bracket. If working on the driver's door, remove the lock cylinder, release the latch assembly wiring retaining clips, and disconnect the wiring connector(s). For vehicles from September 2000, pry the outer cable from the retaining bracket and disconnect the inner end from the lever on the latch. Loosen and remove the latch assembly retaining screws, maneuver it behind the rear window support rail, and out from the door with the latch button linkage. For the front door exterior handle up to September 2000, if working on the driver's door, remove the lock cylinder; for the passenger's door, pry out the grommet to expose the outer handle rear cover retaining bolt, remove the bolt, and pull the outer handle outwards to disengage the latch mechanism. For the front door exterior handle from September 2000, ensure the latch is in the 'installation position', pull the handle outwards, and turn the actuator screw counterclockwise before removing the handle. To access the front door lock cylinder, pry out the grommet to expose the lock cylinder retaining bolt, remove the bolt, and pull the lock cylinder from the door. For the rear door latch, remove the door inner trim panel and sound insulation material, disconnect the door latch wiring connector(s), loosen and remove the latch assembly retaining screws, and maneuver the latch from the door. For the rear door exterior handle up to September 2000, pry out the grommet to expose the outer handle rear cover retaining bolt, remove the bolt, and pull the outer handle outwards to disengage the latch mechanism. For the rear door exterior handle from September 2000, ensure the latch is in the 'installation position', insert the handle into the door, and tighten the retaining bolt securely. During installation, ensure the latch lever is positioned correctly, apply fresh locking compound to the latch screws, reconnect the wiring connector(s), and check the operation of the latch assembly before closing the door.