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Tire presure monitor - why the correct tire?

yukon4wd

By yukon4wd
in Ask A GM Technician

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yukon4wd Enthusiast

yukon4wd

Posted
Posted

Sorry not sure where else to post this.

 

One of the things important with the tire monitor system, is to program which tire is in which position. Let air out, run around reporogram etc.

 

WHY????

 

I had always thought it was so the DIC would indicate which tire had a problem. Well I had a leak, and get a warning that I should "Check Tire Pressure", but not which tire.

 

Why on earth all the hassle with getting the position correct, if it can't tell me which tire has a problem? It just seems a bit wierd to me.

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

I could be wrong, but even though it just says "low tire pressure" and not specifically which, you should be able to scroll through the DIC and display each individual tire/pressure.

 

Even if that's not the case on yours (there are variations), knowing which sensor is in which position can be important when it comes to diagnosing a system problem.

A wheel sensor code may set and we need to know which sensor it was. You wouldn't be very happy if someone wanted to charge you for all four sensors because they had no clue which was the fault one.

 

So though you may not be able to see individual tire pressures, we get a lot of information via the tech 2.

yukon4wd Enthusiast

yukon4wd

Posted
  • Author
Posted
I could be wrong, but even though it just says "low tire pressure" and not specifically which, you should be able to scroll through the DIC and display each individual tire/pressure.

 

Even if that's not the case on yours (there are variations), knowing which sensor is in which position can be important when it comes to diagnosing a system problem.

A wheel sensor code may set and we need to know which sensor it was.  You wouldn't be very happy if someone wanted to charge you for all four sensors because they had no clue which was the fault one.

 

So though you may not be able to see individual tire pressures, we get a lot of information via the tech 2.

 

 

 

 

Thanks for that. My DIC does not offer any tire info at all, though I was expecting it to do so. Maybe I need to search harder, but I think I have tried every option.

 

I didn't realize that they actually measure the tire presure. I had guessed it was just a Too low, OK, too high type thing. It would definitely be nice if there was some way I could see the presure on the DIC, or even if an after market interface was available.

 

again thanks

jojiboy Enthusiast

jojiboy

Posted
Posted

On my 05 Yukon it will display, on the DIC, the PSI for each individual tire. I don't know if you have the steering wheel controls but for mine I press the button that has the mileage symbol until the DIC shows "Tire Pressure" or something like that. Then I press button that has the enter key symbol, each press will show the tire pressure for an individual tire (ie., LF, RF, RR, LR). I can't imagine that your 2004 Yukon would be any different.

yukon4wd Enthusiast

yukon4wd

Posted
  • Author
Posted
On my 05 Yukon it will display, on the DIC, the PSI for each individual tire. I don't know if you have the steering wheel controls but for mine I press the button that has the mileage symbol until the DIC shows "Tire Pressure" or something like that. Then I press button that has the enter key symbol, each press will show the tire pressure for an individual tire (ie., LF, RF, RR, LR). I can't imagine that your 2004 Yukon would be any different.

 

 

 

 

Thats basically exactly what I was expecting, but I couldn't find it. I will take another look tomorow, and see if I missed it some how.

 

Thanks.

Wingnut Senior Enthusiast

Wingnut

Posted
Posted
On my 05 Yukon it will display, on the DIC, the PSI for each individual tire. I don't know if you have the steering wheel controls but for mine I press the button that has the mileage symbol until the DIC shows "Tire Pressure" or something like that. Then I press button that has the enter key symbol, each press will show the tire pressure for an individual tire (ie., LF, RF, RR, LR). I can't imagine that your 2004 Yukon would be any different.

 

 

 

 

That's how mine is.

 

And when one of my tires is low, it bongs at me and displays which one. It then stops it's incessant bonging but leaves the display up until the tire is back at a decent pressure.

drumset5994 Enthusiast

drumset5994

Posted
Posted

Why cant things be simple? I never understood people who let their tires run flat, and say "oh, i just didnt know" ...every vehicle ive ever had for 10+ years, i carried a pen tire guage in the glovebox. You'd be amazed how many people DONT know how to even use one.

 

If i had aluminum rims, i watched more carefully...as the cold/hot day/night would make them leak a little...steel rims, never had a problem...but i still checked them!

 

I bring this up, not to be a post whore, but the boyfriend of the girl im buying the cherokee off of (as a beater) is an idiot. This kid supposidly went to BOCES for auto mechanics...yet he can barely spin a wrench. We got into a discussion one night because he, and i quote...

 

"...im glad i didnt buy a Chevy Silverado with those garbage tranny's ...at least the GMC Jimmy has a better tranny in it..."

 

This is whats leading our world 10 years from now people. LOL

 

Anyhow, sorry. Continue.

yukon4wd Enthusiast

yukon4wd

Posted
  • Author
Posted
On my 05 Yukon it will display, on the DIC, the PSI for each individual tire. I don't know if you have the steering wheel controls but for mine I press the button that has the mileage symbol until the DIC shows "Tire Pressure" or something like that. Then I press button that has the enter key symbol, each press will show the tire pressure for an individual tire (ie., LF, RF, RR, LR). I can't imagine that your 2004 Yukon would be any different.

 

 

 

 

That's how mine is.

 

And when one of my tires is low, it bongs at me and displays which one. It then stops it's incessant bonging but leaves the display up until the tire is back at a decent pressure.

 

 

 

 

 

Well I just changed to Snow tires today, and now I am getting all the warnings again. I marked the rims with chalk, and they definitely put them back in the same positions, but the warning is flashing now and wont go off. I checked the tires with my own gauge, and it showed them all slightly over inflated (about 37 psi) not enough I would think to cause the warning, but I dropped them all to 35, but still the warning. I used the gauge last week to measure the pressure, so I think the gauge is OK.

 

Worst thing is I don't know if the warning is over presure, under presure, wrong rim position, fault somewhere etc. But its very annoying. If I could see what it thinks is the presure in the individual tires, I could do something.

 

Is there some way I can program the unit to get this "hidden feature".

  • 1 month later...
yukon4wd Enthusiast

yukon4wd

Posted
  • Author
Posted

Does anyone know if its possible to program the DIC to let e know more about my tires than "Check Tire Pressure". I am guessing if these tuning guys can control the engine, then checking the tires can't be a big job.

cerbomark Senior Enthusiast

cerbomark

Posted
Posted

the monitor may be in the value stem, so if you changed to snow tires without the sensors being changed you will not get the low tire pressure indicator to go off. I m a little confused on what you changed. You put on different rims too? My 07 has the senors in each value stem. So if I put differtn rims and tires without the sensor stems it will create a problem. Also the 07 shows each tires and the pressure ineach. Does this make any sense in your case?

yukon4wd Enthusiast

yukon4wd

Posted
  • Author
Posted
the monitor may be in the value stem, so if you changed to snow tires without the sensors being changed you will not get the low tire pressure indicator to go off. I m a little confused on what you changed. You put on different rims too? My 07 has the senors in each value stem. So if I put differtn rims and tires without the sensor stems it will create a problem. Also the 07 shows each tires and the pressure in each. Does this make any sense in your case?

 

 

 

 

Hi Mark, thanks for the reply. Basically I had trouble getting rims, so I am taking the summer tires off, and putting the snow tires on the standard 17" alloy rims. I mark the tires to go on different rims, then put the rims back in the same position, so the end effect, is that the Tires get rotated twice a year, but the valves stay in the same position. I had assumed that this way, I get my rotation, and don't have a problem with having to reprogram the sensors.

 

Inside the rim there is a small plastic box, about 2" x 1 1/2" x 3/4" attached to the valve stem. This box is I assume the pressure sensor.

 

Now I had a very slow leak before the change (pressure dropped about 5 PSI over 3 weeks no matter how many miles I drove), and it was consistent over three tire swaps on the same rim, so I assumed it to be a valve, I told the tire place about this, and asked them to specifically check that valve for a leak. I am guessing now that they fond a leak, and played with or wriggled the valve or tightened it to stop the leak (it no longer leaks). BUT I got for about 2 weeks the "Check Tire Pressure warning".

 

Well now it all changed. Yesterday I got a "SERVICE TIRE MONITOR SYSTEM" warning, and the low pressure yellow warning light has disappeared.

 

Personally I think that tire pressure is something that needs to be checked manually, so I would be pretty happy if I could just deactivate the whole system. So basically is there an option to just kill the whole system so it doesn't give me these messages?

cerbomark Senior Enthusiast

cerbomark

Posted
Posted

Don t know about shutting down the whole system? To re set the system you let air out of each tire until the warning comes on for each tire (guessing about 20-30 lbs). Then just re air them and they should re set each one in the correct loction.To do this I would get a pressure gauge and of coarse air.

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