# Tire pressure electronic read inaccurate



## Hazlitt777 (Nov 2, 2013)

On our data screen one can find a readout on the tire pressure. I love it. The problem is that it seems not to be accurate anymore. My passenger front tire reads as being two lbs below what it actually is.

I've checked them and they are all at 37 lbs according to my manual gauge. But when I check the electronic read on them, they are all 37 with the exception of the front passenger tire. 

As I drive it and the tires heat up, that front passenger tire still lags behind the others.

Any suggestions? Is there a sensor that is dirty...and if so where is it so I can clean it.

Am I even in the ballpark here. 

Thanks.


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## ChevyGuy (Dec 13, 2014)

Hazlitt777 said:


> Any suggestions? Is there a sensor that is dirty...and if so where is it so I can clean it.


The sensor is inside the tire. You'd have to dismount the tire. I'm not sure as there's anything you can do with it other than replace it.


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## Robby (Mar 1, 2013)

I run into this from time time......dunno why. Anyways, if I perform a relearn using the tool the readouts become accurate again.

As far as the why does it happen????? I can only guess it is related to all the radio signals (cell towers, phones, other cars leaking RF)...things of that nature. Quite simply, the monitors in the wheels are nothing more than transceivers (they receive a 'report' signal ans send a 'result' signal to another transceiver in the car). But with all the other electronic 'noise' going on you can see how it might 'infect' the readouts.

Rob


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## Hazlitt777 (Nov 2, 2013)

Inside the tire...as on the inner side of the rim? I won't both with it then.


ChevyGuy said:


> The sensor is inside the tire. You'd have to dismount the tire. I'm not sure as there's anything you can do with it other than replace it.


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## Hazlitt777 (Nov 2, 2013)

How does one do a "relearn?"


Robby said:


> I run into this from time time......dunno why. Anyways, if I perform a relearn using the tool the readouts become accurate again.
> 
> As far as the why does it happen????? I can only guess it is related to all the radio signals (cell towers, phones, other cars leaking RF)...things of that nature. Quite simply, the monitors in the wheels are nothing more than transceivers (they receive a 'report' signal ans send a 'result' signal to another transceiver in the car). But with all the other electronic 'noise' going on you can see how it might 'infect' the readouts.
> 
> Rob


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## ChevyGuy (Dec 13, 2014)

Hazlitt777 said:


> How does one do a "relearn?"


First, you have to have the tool. The process is outlined in the owner's manual.

The other option is to go to your local tire place and see if they'll do you a favor. They should do it if they rotate your tires.


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## Eddy Cruze (Jan 10, 2014)

Hazlitt777 said:


> How does one do a "relearn?"


I thought my system was just very inaccurate to then learn those 4 free new car Rotations came with no reprogramming of the tires and made it very difficult over a 3 year period. The Tech who set them on my last visit clearly doesn't do this as part of a routine Rotation, took about 15 minutes with my Service writer sitting in my car and I watched how accurate those sensors function one by one, took about half a minute to correctly read out after setting and airing up, impressive!


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## Taxman (Aug 10, 2017)

Eddy Cruze said:


> I thought my system was just very inaccurate to then learn those 4 free new car Rotations came with no reprogramming of the tires and made it very difficult over a 3 year period.


When I took my 2016 to the dealer for an oil change, I heard a horn in the shop. The lube tech had rotated my tires and somebody else was walking around my car with the learn tool after taking my car out of the lube bay. I only asked for an oil change.


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## ChevyGuy (Dec 13, 2014)

Eddy Cruze said:


> I thought my system was just very inaccurate to then learn those 4 free new car Rotations came with no reprogramming of the tires and made it very difficult over a 3 year period.


Good point - OP, check all of your tires. It's possible the display is showing the wrong wheel. The computer is completely dependent on the learning process to know which sensor goes with which location. If it was done wrong, or the tires rotated without a relearn, the display will be wrong.


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## Hazlitt777 (Nov 2, 2013)

I rotated my own tires. This wasn't the first time. Yet, this time was the only which caused a problem.


ChevyGuy said:


> Good point - OP, check all of your tires. It's possible the display is showing the wrong wheel. The computer is completely dependent on the learning process to know which sensor goes with which location. If it was done wrong, or the tires rotated without a relearn, the display will be wrong.


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## ChevyGuy (Dec 13, 2014)

Hazlitt777 said:


> I rotated my own tires.


Do you do a relearn? If not, then the displayed location is inaccurate. I'd suggest you check all 4 tires. There's a very good chance one of your tires is low - it's just not the one indicated in the display.


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## mechguy78 (Jun 6, 2016)

Hazlitt777 said:


> I rotated my own tires. This wasn't the first time. Yet, this time was the only which caused a problem.


Given our cars require a relearn at every tire rotation, I purchased the tool earlier this year due to doing my own tire rotations myself as well. If found my tool on amazon for around $20. 

Here is a link to the tool. 
https://www.amazon.com/gp/aw/s/ref=is_s?k=el50448

up until getting my own tool, I would drop by my dealer and they would do the relearn for free. My only problem with doing this was that it was a 45 min drive to get there just for that.


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## Taxman (Aug 10, 2017)

I bought my EL50448 from China. I forget who the seller was, but last year I was happy to pay $11. The one I got didn't come with a 9v battery, but worked great once I put a battery in it. EDIT: I just checked, and the seller I bought it from, CARATDIAG, doesn't have anything listed in their ALIExpress store now. 

They're really cheap now, I see them as low as $8.


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