joebuckSR

is the only way you know that they work is putting them on the car or is there a way to know without putting them on the car.

Flame Red

It is pretty hard to figure out if they work without having them on the car. The car will not look for their signal until it reaches a speed where the sensor's rotational motion generates enough current for the sensor to put out a signal.

They way you generally test them it to fill up all the tires to 30 lbs and you should get no low tire signal at cruise speed. Then you lower the pressure for each tire to 25 lbs and take it for a cruise and you should get a low pressure light. Then you fill that tire up to 30 lbs again and proceed to the next tire. You can pull the code and it will tell you which color sensor is giving you the low tire warning, and then it is smart to mark that on the wheel for the next time.

If the system does not get a signal from one of the sensors it will post a code and you can pull the code to figure out which color sensor is the problem. However, if you don't know which color sensor is on which tire then you have to figure it out where the bad sensor is mounted!