I'm running my tire pressure at 27 psi Front/ 31 psi Rear per the Porsche TPMS system (29/33 actual per my tire gauge) and after re setting the TPMS it still continues to show low tire pressure with warning light. The tire pressure is registering on all 4 corners but system is generating a warning light which is an annoyance. Is this a battery issue or something else?

 

My car same thing....most have said it's the batteries.

 

dealer has a tool that reads battery level without taking sensor out.
try that first

 

Mine is the same way, my tire pressure always shows lower than the actual with a tire gauge. I have two sets of wheels/tires, one has new tpms, both always show low. I always have to add extra air just to keep the warning light off.