So this morning I put the real spare (no TPMS) on and put one OEM tire in the trunk. A full-size wheel & tire fit okay in the hatch, it only sticks up a bit.

After a few miles the TPMS light went on, I assume that it's no longer getting a signal from the tire in the trunk. Perhaps the TPMS sends a signal only when the tire's rotating...

I can live with taping over the TPMS warning light and with having only three of the four tires with TPMS. But does anybody know if I'll still get a warning if one tire loses pressure, if the TPMS light is on?

 

Yes, the sensor only sends a signal once you reach 28 mph, presumably as a battery saving measure.

 

Where did you get the info about the 28 mph sensor reading?

 

The fact that it's to save battery came from my nether regions. The 28 mph to activate the TPMS sensor sender came from the factory service manual.

 

also the fact you have a flat would send a signal? just sayin..

 

Don't have a flat, just swapped tires as part of rotation. Just called the dealer, they said if there's a fault because they're not receiving one sensor, the system won't indicate any flats. So essentially I'm without TPMS 4/5 of the time. Good thing I own like eight tire gauges...

 

got ya, sorry i re read what i posted wasn't trying to sound like a jerk if it came out that way.