Movano B bonnet will not latch and lifts while driving

A bonnet that needs several attempts to latch, vibrates over bumps or rises by a few millimetres at higher speed does not merely need adjustment: its latch is worn. On a van opened several times a day, the latch mechanism operates far more often than on a passenger car. Once dirty and corroded, the catch no longer holds the striker securely. Ignoring this symptom is dangerous. If the bonnet opens fully on the road, it bends at the hinges and damages the cab roof and windscreen.

The prop rod drops and the bonnet closes by itself

The second common fault in this area concerns the bonnet prop rod. A worn retainer or distorted rod no longer holds the bonnet securely, allowing it to fall during servicing. The part is inexpensive and takes only a few minutes to replace. At the same time, inspect the bonnet safety catch, which retains the bonnet if the main latch releases. A worn or bent catch can no longer do its job, even though it is the last barrier preventing the bonnet from opening while driving. When fitting a new latch, adjust the striker height so the bonnet sits flush with the wings and latches without being pressed down. The latch and striker should also be cleaned and lubricated periodically. In most cases, dirt rather than mechanical wear is the original cause of poor latching.