The tire pressure monitors (tpm) are programmed into the cars computer.  What happens if you have two sets of tires and both sets of tires have TPM installed, would you have to have the computer reprogrammed to recognize the TPM each time you change winter to summer wheels?  What would be the point of having sensors that are different from one xB to another.  I would think that one xB wheel should be able to be installed on another xB and the computer will still be able to read the signal.

How many different TPM's could there be for the xB?  Scion would want to keep costs down and just stock one part number and not many.

Am I reading this system wrong?

Thanks

This question is for the guys (or Gals) who have two sets of rims and tires.  Do you also have a second set of sensors or do you do the sensors in the pressurized tube thing?

if there are 2 sets of pressure sensors, there are 2 options, 1 - put the ones that are on the car now in the new wheels and tires, 2 - install new wheels and tires with the second set of sensors but they would have to be programmed IF you didnt want to see the flashing tire light on the dash.

I have aftermarket wheels and my sensors fit in them so i didnt have to program them. I bought my wheels from tirerack.com and when you are looking at rims they tell you if the rims support the sensors.

hope this helps!

Hellen - maybe a nail or something in one of your tires? Also, check your tire pressures and make sure they are set close to the driver door jam. My light comes on too when it gets really cold overnight.

Hope this helps!

Here's a comment from a Subaru site that pretty well sums it up...

Tire Pressure Monitoring Systems (TPMS): Cold weather causes tire air pressure to drop. If the TPMS light is on in the morning but goes out after driving a few miles, the low pressure warning is probably due to the colder weather. Adjust your tire pressures for the seasonal change.

I'm confused, do the wheels you have on now have a sensor or not? I put my steelies on for the winter with no sensors and my warning light stays on. If you have wheels on the car with no sensors, your warning light should be on. If it isn't something is wrong with your monitoring system.

i have confermed that there are not TPMS in the rims. The guy i bought the rims from said that he didn't have them on the car the rims where on.

This should be an interesting thread.  The light is on, the light is off.  With sensors, without sensors.  Can't wait to see how this all works out.  Me I like the sensors in the tube thingy.