
The air vents failing to rotate upon startup, caused by an inferior plastic cog inside the motor
The Jaguar XF's have a unique feature where the interior air vents rotate upon startup, a great feature when working correctly. Unfortunately the cog which mates the rotating mechanism in the air vents to the motor is made of weak nylon and has a poor structural design, this cog can snap which causes the rotating mechanism to fail.
The cog has a large cut-out, to visually inspect if it is mated correctly. However this cut-out provides structural weakness and often snaps here. The cog also has a thin and weak stopper which breaks and is the most common reason for failure.
Jaguar have recognised this fault and have begun to sell the cog (known as a "stepper motor clutch") separately, however the part is scarcely improved and the fault will reoccur time and time again.