hey guys,
I had the same problem two nights ago - I was on my way home from work that I noticed that the low pressure light was on so I stopped to get the air checked, got them filled with the right amount of air ... but the light seemed to stay on till i got near my home. i checked the manual and it said that the signal will go off once the newly air filled tires got warm and expanded. Try jotting down the times you have them filled with the right amount of air and how much the light stays on and when it goes off