There are two different kinds of TPSM, direct and indirect. The indirect system does not actually give you tire pressure, instead it notifies you if any of the tires are rotating differently or out of the norm. With direct TPSM, the tire pressure is tracked and notified if under operating pressure. We specialize in installing direct TPSM sensors to increase the safety of your driving experience. With our module that can be viewed inside your car, you are able to monitor the PSI levels accurately.