Calamity of ignorance. Purchased 4 tires in April. Tire sensor light stays on and tires losing air slowly. I have an expensive digital gauge. Brought vehicle in. Tire guy has $0.99 store tire gauge and tells me none of my tires are low. I show him rains from mine and he says he must need a new gauge. Then he hooks up computer and does not know how to operate read it so he goes and asks someone else. Comes back and says 3 of 4 tire sensors need to be replaced. Didn't sound right so I went to Bridgestone. They determined computer not reading sensors correctly and 30 min later all is fixed and sensor light is no longer on without replacing 3 sensors @ $70 a piece. Not impressed at all.