Regulatory Changes: Initially, a TPMS fault was categorized as a minor defect, but changes in regulations in June 2019 reclassified it as a major defect. This means that any vehicle with a malfunctioning TPMS will fail the MOT due to safety concerns.

Importance of TPMS: The TPMS is crucial for monitoring tyre pressure, which is essential for vehicle safety. A functioning TPMS helps prevent tire blowouts and improves fuel efficiency, making it important for vehicle owners to ensure their TPMS is operational to avoid MOT failure.