my tpms light started flashing a week or so ago. i checked the tire pressures and they seemed fine but the light stays illuminated anyway. i checked the manual and it seems to suggest that the system itself may be malfunctioning--apparently, if it blinks for a minute when the car is turned on and then stays on the system may be down. i'm going to stay away from the fact that it is really annoying that it is all but impossible to tell the "low tire pressure" warning apart from the "system not working" warning and ask only, "has anyone has had this happen before and how expensive a fix is it?". if i'm generally good at staying on top of tire pressure do i need to fix it if it's an expensive repair?