Norm Peterson

It's like JAJ said - if you start up near enough to the stack of tires you just took off, the TPMS won't flag any problem until you've driven 20 miles or so.

As to what constitutes "near enough" . . . when I've got my non-TPMS summer tires/wheels on (see avatar pic), I can start my car without getting a TPMS fault up to at least 40 feet away, so I'd count on at least 30. I'm well into the second full season on the summer setup, plus a few weeks toward the end of 2010 and the TPMS has behaved the same all three times.



When I do go more than just locally, it's just another minor nuisance, another button to push after shutting the TC off, and another silent "up yours" to all those regulators who don't think I should have to think for myself.


Norm

157dB

What about the sensors 'sleep mode'.
Would one not have to rotate the tire
stack to activate the TPMS sensors
and 'wake' them up before starting the
stang?
Same thing with stuffing the sensors in
PVC and airing the whole kit and kaboodle
up to 34 PSI to satisfy the TPMS system?
Shake the PVC tube while driving to get them
'awake' and reporting PSI status?
The 'sleep mode' is a biatch...

Norm Peterson

In practice, sleep mode does not seem to be a problem as far as start-up is concerned. I don't even move the stack of OE 235/50-18's more than once or twice the whole time I'm on the summers (8 or 9 months, actually).

After the ~20 miles, it does flash 'FAULT' (I've got the message center), and after returning home it takes a couple of starts before it realizes that I'm near the stack of OE tires.


Norm

157dB

I dont understand this.
Support your claims with more detailed info.
Or are you just using the "FAULT" message
as an indicator?

Norm Peterson

You don't have to first roll the car before starting it when the TPMS tires are mounted on it, do you? No, they get pinged from the module and reply.

I can leave my stack of OE tires completely untouched for several months at a time, and as long as I consistently start the car up within range and keep my total trip distances short enough it's like I never took the TPMS-equipped tires off the car. I took a 300 mile trip in the Mustang recently and was gone for a few days. Had to hit reset on every startup as well as on the >20 mile runs, but once back home and after a couple of startups in the driveway everything was back to normal.

I accept the occasional need to hit 'Reset' as the price I pay in nuisance for not spending about $1100 for $750 worth of tires. No big deal, I was mentally ready to deal with it going into putting my summer wheel/tire package together.

I don't know if the PVC tube trick keeps the TPMS silent or not. Maybe if the tube rolls around in the trunk enough to make the sensors think they're in tires that are rolling? Meh, that looks to be more nuisance than the occasional need to hit 'reset'.


Norm