I don't know about how it can detect tyre diameter but i do know it goes mad if your tyres becomes over inflated. My two front tyres became a little over pressuered due to heat expansion and as a result set off the tyre warning - this scared the bejezzuss out of me as i was comortable cruising at 3000 revs in 5th on a motorway - when i pulled over and checked my tyre pressures with a digital gauge ( i never trust analogue ones) my front two tyres were at 34psi and my back pair were at 28 - this difference meant the system activated. Mini One Chilli red with 15 inch pepper pot alloys, ASC+T, alarm, Salt and TLC. If you see me - SL51 MWW - gimme a flash of your lights!! |