Tire pressure monitor in car vs. iPhone app

[Fogey]

Just put a little air in my tires. Original reading in car was 36 in3, 37 in one. (I have since let a little air out of the 37 pounder). Before doing that, I used my iPhone to check pressure (did update first) and it showed 3 at 35 and 1 at 36. I lb down from car reading on all tires. I have just ordered a decent pressure guage from Jegs. Should be here in a few days. So I can check things out, but just wondered if anyone else has had this anomaly between the car and the iPhone readings?

[LoneStar]

I believe that the app shows the tire pressure from the last time the car was on. (Although the app shows me having two more miles than the odometer does... )

[Fogey]

Took a drive this afertoon. Car showed 36 all around app shows 35 all around.
Don't really care, was just curious if others had experienced the same thing.

[PQ]

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are you talking about?

[binlow84]

Originally Posted by PQ

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are you talking about?

I believe he is referring to different readings being reported by OnStar in his MyLink iPhone app than what is displayed in the DIC for his tire pressure.

Until GM finishes the 2010 fix and I can get the app from the Android store I can't say. However, my guess is that, as previously mentioned, the tire pressure reported by the app isn't constantly updated. That would require a bit of bandwidth (both for the OnStar unit and your phone) and would likely be impractical. The car probably updates OnStar periodically and that's what the app pulls down.

[PQ]

Originally Posted by binlow84

I believe he is referring to different readings being reported by OnStar in his MyLink iPhone app than what is displayed in the DIC for his tire pressure.

AAAAAHHHHHHHHH...............................

Right.

Well, iDON't know about that.

I got too early of a car. I can't utilise that.

SUCKS.........

[LoneStar]

Originally Posted by PQ

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are you talking about?

The OnStar MyLink app. You know, the app that left the 2010's in the dark ...

[Fogey]

Before airing up the tires, I had DIC and iPhone readings 34,34,33,32. They agreed. After airiing up and driving a bit is when I got the 1 lb per tire difference. The tires, as far as I know, never were at 35 all around so it isn't a case of OnStar not updating, I don't think. Anyway, as I said, not important, just a curiosity.
And an apology. I forget that 2010s don't have the OnStar/iPhone app.

[binlow84]

Originally Posted by Fogey

I forget that 2010s don't have the OnStar/iPhone app.

Yeah yeah, rub it in :P. Anyway, as I think about it more, the discrepancy has to be caused by the app being periodically updated. Both OnStar and your DIC get the pressure from the same source, the TPMS' installed in your tires. The reading beamed to OnStar is the same reading showed in your DIC, but may be outdated by the time it is beamed to your phone.

[C586]

You need to resyc the car to the app once in a while. All the readings are taken from the same place so they cant be different. Open MyLink and at the top right under the white bar is a refresh symbol. Hit that and everything will be correct.

[Fogey]

Under the white bar there is a curled arrow on the left hand side that I thought ws the refresh button. It is the only thing that looks like it does anything. When I hit it, it says "updating from Camaro". I just did that and am sitting in the car with the DIC showing 36 and the iPhone 35, all around. Either my DIC or iPhone is posessed. Better than reposessed I guess.

[Fogey]

Under the white bar there is a curled arrow on the left hand side that I thought ws the refresh button. It is the only thing that looks like it does anything. When I hit it, it says "updating from Camaro". I just did that and am sitting in the car with the DIC showing 36 and the iPhone 35, all around. Either my DIC or iPhone is posessed. Better than reposessed I guess.

[binlow84]

Again, it is unlikely that the OnStar estimate is in real time. The intended usage of the OnStar app is to get the information when you don't have access to your vehicle, not while you're sitting behind the wheel. There is no reason to update the information in real time given the cost of doing so, making periodic updates the most likely method used.

There is nothing wrong with your OnStar app or your DIC, they are both working as intended.

By the way, I realize while rereading this is sounds kinda "snippity," but that wasn't my intention, so please don't take this the wrong way.

[Cam2011]

Originally Posted by Fogey

Just put a little air in my tires. Original reading in car was 36 in3, 37 in one. (I have since let a little air out of the 37 pounder). Before doing that, I used my iPhone to check pressure (did update first) and it showed 3 at 35 and 1 at 36. I lb down from car reading on all tires. I have just ordered a decent pressure guage from Jegs. Should be here in a few days. So I can check things out, but just wondered if anyone else has had this anomaly between the car and the iPhone readings?

You let out a pound? What are you running Talladega?