My car flashed the low pressure warning today. The psi is suppose to be 30 when I checked the tire it had 28 pressure in the tire. Are they suppose to trigger a warning with only a two pound differance

 

Perphaps the cold weather triggered the light, per


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To begin; are the positions accurate? Did you check them all? With a gauge?

Is there a problem with it warning you?

I think it works on a percentage difference.

 

I did check them all with a digital tire gauge. Two were at 30 one at 29 and the 4th was 28. I assume the 28 was what turned the low pressure light. I guess I thought it would take like a 4 or 5 pound lower reading before it would turn the light on

 

What did the DIC indicate the pressure to be? I had a temperamental sensor, would occasionally indicate a problem with RF. Sometimes the DIC would show dashes -- -- on RF. Actual pressure was always fine. Next time I bought tires, I had the sensor replaced. It's been about 4,000 miles and over 3 months, no problems. The sensors are battery operated and the batteries are not replaceable.

 

My '08 HHR SS still has the original TPMs in the original tires(37800 miles). My winter tires I bought back in 2009 also have the original TPMs(bought for the winter tires) in them as well. What would be the expectation for those batteries life? 7-8 years seems lengthy on any battery run device.

 

My '08 LT has the original TPS valve stems after 78K miles....still works ok.
I will replace all 4 of them on the next tire rotation and balance, not expensicve enough to be concerned about it and will save much trouble later on.
Just saying.

 

The stems are only about $5 each, but the TPM is much more expensive around $15 each on eBay; GM wants about $80 each. You can't replace just the battery.

 

Thanks my friend, I appreciate it!

 

BTW, the reason I cite the MSRP is because that is the least that a tire store will charge for the parts, plus exorbitant labor.