Have an 07 Cayman S with about 4k miles on the clock. For the last week, I've had the TPMS "soft" warning indicating certain tires were 4 psi low. It alternated between just the left front and both left front/left rear showing low. I manually checked the tires with two guages and they all looked fine (32 front / 36 rear with 19"). Also, the pressure readout (one available while driving) read that the two fronts had equal pressure and two rears had equal pressure (contradicting the warning that the left tires specifically were low)

Took it to Park Place Dallas today for them to look at. Service guy told me a couple things people might find interesting
1. Surprising you are here, we never have problems with the TPMS
2. Throw away your manual pressure guage. you have a $60k pressure guage
3. The two screens that indicate pressure don't "talk to each other". The one available while driving (mixed in with average MPH, MPG, etc.) is not accurate. The one where you have to go to TPMS menu option and have to be stationary is accurate and adjusts for things like temperature. That is the one to trust above anything

They topped tires off and the "accurate" reading stopped complaining (haven't had a chance to see what it manually reads at). Just throwing that out there for comparison purposes.

Service guy is wrong. If you do some searching here, you'll find a lot on how TPMS works and it is measuring absolute pressure which is different than the pressure a tire gauge measures which is the value you want.

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Robert

I seem to be having TPMS problem right now... -7 low on left rear. I need to take it in because no matter what I do it will not reset.

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Kevin

If it is a constant -7 there is a very good possibilty of a leak in your tire. Have you examined it? Also it could be a bad sending unit so if you have no leak take it in.