[/quote]It would be nice if that would work, however the sensors are normally off if they are stationary. They only turn on and transmit while the wheel they are mounted to is rolling (over 25mph). Just having them sit in something pressurized wouldn't work unless you could get them rotating fast enough to turn on as well[/quote]
Well, I guess this is where the accessory powered electric motor comes in
On another note, now that I have my winter tires installed on my Tarmac IIIs without TPMS, the TPMS sensor on the dash will begin flashing for about a minute before it comes on steady. With the stockers, it never flashed, as I recall, and only came on briefly during start up. Someone who still has the stockers with the TPMS please try this (or I will this spring, when the stockers go back on). Start your car and drive in a parking lot and never exceed 25 mph (would be lucky to hit 10, usually). Does your light go on, not go on, blink, not blink? If the TPMS doesn't start sending until 25 mph, is the default not to flash at all?
I would think the ECU would also have to be able to detect the presence of the TPMS unit prior to motion, otherwise I should have experienced the flashing prior to the tire/wheel swap (until of course I hit 25 mph). I think the fact that it is no longer within range to send a signal would let the ECU determine(by absence of a proximity signal) it is not present, hence the immediate flashing, to differentiate between the absence of the transmitter(flashing) versus one that has not yet been activated by speed(no flashing).
Anyways, enough with this and somebody please find a solution before I put my daughter's Hello Kitty sticker over the dashlight