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Tire Pressure Monitoring System (TPMS)

My TPMS light comes on about 75% of the time. (That’s not the light for low pressure.) I took it in to the dealer once and they replaced the valve stem in one tire. It continued to come off and on intermittently. This time the dealer said they needed reprogrammed. It still continued. This time, they said there was no evidence of an error message while running diagnostics. They told me to just ignore it from now on. Should I expect this as the final answer?

Is this vehicle under warranty?

The TPMS light is the ‘Tire Pressure Monitoring System’ light, right? So that would seem to be the low tire pressure light. Do you have a spare? Do you check the tires first thing in the morning when they’re cold, with a good quality gauge?

You should not expect this as the final answer. TPMS systems have been mandatory on all light duty vehicles for a few years now.
The system is there to warn you of tire inflation problems.
When they told you to ignore the warnings, that was code for "we don’t know what’s going on. Go away and don’t bug us with this again."
You should find a shop that is capable of diagnosing it.
This one clearly isn’t.

texases – On the one car where I had to deal with a TPMS ('08 Civic), the “TPMS” light was the self-test light that indicated the system was working. There was a separate low-pressure warning light. (Had me confused at first, too. I have it posted here somewhere.)

My low tire light comes on when the temp is below about 20 degrees, but the tire are only about a pound low. The light goes out when the temp rises. It does make one wonder tho if the tires are really low.

EllyEllis wrote:
My low tire light comes on when the temp is below about 20 degrees, but the tire are only about a pound low.

TPMS systems are usually set to come on at a much lower threshold. Are you sure that your gauge is accurate? If it’s the cheap pencil type, it may not be. Does your TPMS system tell you which tire or tires are low? Depending on the car, it may be reading your spare tire, which perhaps is much lower than the others.

It could be that you have a bad sensor in one wheel. How old is the vehicle? Have you had tires replaced and, if so, was the light coming on before the replacement? TPMS sensors need to be rebuilt or replaced at every tire replacement and, in some cases, more often (if you replace tire infrequently).