to save a few bucks from having summer tires and snow tires mounted and remounted on the same 4 rims each spring and fall I purchased 4 extra rims and now have dedicated winter and summer rims as well as tires. All rims have Toyota valve stems that the dealer assured me would work with my monitoring system. The snow tires are on the original rims with the original stems that came on the truck. This is the second winter for these tires. I installed the snows myself and went to the dealership to have the system reset to the different valve stems from the summer rims. I was surprised by a $45.00 charge (which means I am saving nothing) and was even more surprised when the systems warning light came back on as I drove home. I have been back to the dealer (who tried to charge me $80 for the second visit) and they again reset the system but this time told me that the module that controls the system may be defective. The light came back on even sooner this time. I telephoned Toyota USA and explained my problem and they said that I should not be having this problem (well duh !), but that the warranty was up and maybe I should get a second opinion about my problem from another toyota dealer. I have put electricians tape over the flashing light for now, but am a bit upset because this is the first vehicle in my life that was purchased new and I thought I would live happily ever after (especially with a toyota)