"Check Tire Pressure" message mystery

[Am_Dew]

For the past two mornings, when I started my '05 XLT (6 cyl) the message "Check Tire Pressure" came up in the message/info center as well as the low tire warning symbol displayed on the instrument cluster. I immediately checked my tires and the pressure was 32 psi on all of them. I hit the 'reset' button on the message/info center system and proceeded to drive away and a few miles later the low tire warning symbol on the instrument cluster went off and the "Check Tire Pressure" message did not come back.

Since my tires were all fine, what caused the warnings to display?

The only thing I can think of which caused these warnings to come on was the fact that it has been abnormally cold in the morning...mid 20's, and that was somehow affecting the sensors.

Does anyone know how the "Check Tire Pressure" system works? Are there special valve stems installed? Are there sensors that sense when the vehicle is not level?

 

[ffdemoss]

I immediately checked my tires and the pressure was 32 psi on all of them.

Most likely the cold...but for a 2005 the air pressure is 35 psi. See your fuel door.

 

[robbie51981]

Most likely the cold...but for a 2005 the air pressure is 35 psi. See your fuel door.

Yes, pressure is supposed to be 35psi. There are special & very expensive valve stems in your tire that monitor the pressure. It is most likely the cold weather causing this alarm. The pressure lessens the colder it is and when your tires warm up the pressure increases. Your tires could be reading 30psi first thing in the morning but 5 minutes into the drive read 35psi because of the heat generated from the moving tire. Increase all your tires to 35psi cold and see what happens.

 

[Am_Dew]

Thanks for the replies. I will increase the PSI to 35 and see what happens.

Re: these expensive valve stems that monitor the pressure...what happens when you buy new tires?

 

[robbie51981]

you can reuse them...just make sure they dont take them out thinking they are regular stems or break them. if so your light will stay on for good.

 

[jrford]

I once talked to an engineer. . .the problem is not the pressure, but the Battery in the Valve Stem that gets to cold to put out the proper signal, thus the truck thinks there is no pressure in the tires. Once the tires heat up the signal returns.

 

[Am_Dew]

I once talked to an engineer. . .the problem is not the pressure, but the Battery in the Valve Stem that gets to cold to put out the proper signal, thus the truck thinks there is no pressure in the tires. Once the tires heat up the signal returns.

Interesting. Thanks jrford. In any case, once I hit reset and drive for a few minutes, all warnings are gone and don't come back until the next morning so it surely has something to do with the cold.

 

[johnskurka]

Same thing happens to my truck when it's cold. A battery in the valve stem - huh.

 

[prerunner02]

35 psi for all 4 tires?

my 02 requires a different pressure for the front 30psi and 35 rear.

 

[Am_Dew]

Sure enough, today when the temp this morning was warmer than it has been ever since the message has been appearing, the message did not appear. If this is in fact due to the battery in the valve stems, what a flop...I mean Explorers are often owned by people who live in cold climates...DOH!

 

[pear]

Ok while we are on the subject.... I have a 2002 EB. Can I buy the sensors and have the added, and have that feature, or do I have to add something in the dash to read them? Thanks, in advance, "pear"

 

[robbie51981]

im pretty sure you would have to have a hookup for it. otherwise since you dont already have them your low tire light would be on your dash. i dont know how hard it would be to install...that may be worth looking into. I believe the last I heard though they were about $100 each...I would rather check it myself once or twice a month for that price.

 

[ExplorerDMB]

http://www.explorerforum.com/forums/showthread.php?t=137498

You can't buy the sensors and just have the feature. Theres another computer you'll need that'll received the signal.

-Drew