And from todays Times -
Thousands of motorists could be driving with dangerously under-inflated tyres because their car’s warning system fails to alert them to a loss of pressure, tests show.
The systems passed legally required trials in laboratories but repeatedly failed to operate on the road in results that campaigners say have strong similarities to Volkswagen’s diesel emissions tests scandal.
A VW Golf failed to detect an under-inflated tyre in 14 out of 16 real-world tests and a Fiat 500L failed all 16 tests, according to research by an independent company commissioned by the campaign group Transport & Environment (T&E). Under-inflated tyres have more contact with the road, which can result in overheating leading to premature wear, tread separation and sudden loss of pressure. It can result in blow-outs and cause fatal crashes.
All new cars since 2014 have to be fitted with tyre pressure monitoring systems (TPMS) that pass official type approval tests. Some directly measure the pressure in each tyre but other, slightly cheaper, indirect systems are supposed to detect pressure changes by comparing the wheels’ rotational speed. The problems detected by T&E relate to indirect systems, which the group says are unsafe and can lull the driver into a false sense of security. Drivers might assume that no warning light meant that there was no problem and fail to check their tyres as a result.
T&E commissioned the Spanish company Idiada to test a rented VW Golf 7 and Fiat 500L. The TPMS warning light appeared within the legally required ten minutes under the conditions set for the official test. The system failed, however, to detect the same under-inflated tyre when the cars were driven in various ways on a test track, including at 30mph and 60mph. The cars also failed to alert the driver that the system was malfunctioning, as they are required to under EU law.