I wasnt entirely sure where this post should go but this section seemed right since it is a gauge sensitity question.

Yesterday while driving my tire pressure monitoring gauge went off.
The day before I had changed over to my snow tires.
The manual says that “significant” changes in tire inflation would cause the gauge to light. I measured the pressure and it was only one pound off from the recommended pressures for rear wheels found on the tag on the drivers inside the door well. (it was 29 instead of 30)
Has anyone had this experience? Is the monitoring system that sensitive ?
To me one pound isn't significant.

 

There's a couple of possibilities.

One is that you had a bead "burp" for some reason and lost the pressure suddenly. Pressure alarms can go by the change in level, or by the rate of change. A sudden loss of 3% of pressure might set the alarm off.

The other possibility is that your monitor "burped". Since pressure transmitters are electro-mechanical devices, they can be fooled by vibration. You might want to double check that tire for balance or missing balance weights or something.

Other than that, I have no idea. What I have posted is just idle speculation based on industrial pressure monitoring. I have no experience with automotive systems.

 

-By tire monitoring guage do you mean that you have a light on the dash that has come on to indicate a low tire or something else. If you have a light then there are two different kinds of monitoring systems passive and active.

-I dont know what kind of vehicle you have i would assume it is a ranger but you never know. A passive Tire Pressure Monitoring System or TPMS measures the tire height. A low tire will not be as tall as an inflated tire and that will trigger the light. If all the tires are equally low the light will not come on.

-An active system uses a remote air pressure sensor in each tire/wheel assembly that measures the pressure in the tire. If a tire goes below a preset pressure the light is triggered. Some vehicles will also give a light if the pressure is to high.

-I work at a tire store and deal with this everyday but I have yet to see a ranger with TPMS and haven't seen a Ford with an active TPMS system. I know in other Ford vehicles with passive systems that there is a reset button on the dash.

-1 pound will not set off the sensor but if you have changed the tires more then likely you will need to reset the system.

 

My tire pressure dummy light comes on after every major temperature change. But it's a good reminder to recheck each time is at recommended pressure. Remember to check them at a consistent temperature. Driving any distances will raise the pressure up a few pounds.

 

Get a signature, we'll be able to help you out better if we knew what you drive.

 

Oh sorry about the signature and not mentioning my vechicle type,I am still not familar with all the features of this forum. It is 2007 Ford Ranger XL which has an tire inflation monitoring system built in. Today I made all the tires equal pressure at 30 lbs. The light then went off. This light just suprized me because of the owners manual. The manual says "significant changes". These tires were just a lb. off the recommended pressures..Thanks for your replies..

 

Just enough I guess. But I didn't know the 07 added TPMS

 

ya, i deal with thoes all the time at work usually explorers tho.
we set them about 2-3 lbs over and take it for a drive down the street. light usually turns off.
with the weather getting colder in michigan, i usually put a little more air in so when i drive out of the shop, its about right.

 

I guess after thinking about it a while maybe it just sensed the difference between my old summer tires and the new snow tires and just triggered the light.

 

but also i wouldnt go buy wat the psi is on ur door jam...i would go buy wats on ur tires

 

Do 2006 rangers come with a tire pressure monitor system?

 

tires are general there is no read out on the tire that says use this PSI for a ranger/jeep/f-250. the MAX psi labeled on a tire is just that MAX.. you shouldnt exceed that it doesnt mean fill to that point and your good to go..

the PSI on the door/fuel door depending is a # derived by a calculation from the tires that come stock on the vehical what PSI SHOULD be run in the truck for THOSE tires...

see tires have something labeled on them that reads like this... "tire can support 2500lb at 55PSI".. now say you drive a reg cab 4cyl ranger which weights right around that amount. that means that 1 tire can support the WHOLE vehical weight at 55PSI... there is a calculation, i cant remeber it for the life of me but taking effect the vehical weight with how much the tire can hold at a curtian psi you will get what psi the vehical should be running. i found it once worked out my truck with my old 265 and came out with right around 32psi...

so your statement of run what the tires say well its true and false the tire do tell you what to do, but you have to do some figuring out.. if the guy is still running stock or a tire with a similar to stock load rating then he should run what is said on the doorjam/fuel door

 

i dont think so.. that system is used in conjuntion with the computer that has the read out on the insterment cluster of "system check" the rangers dont have that screen so i highly doupt they have them.. BUT the 07's might.. idk if Ford cares enough to install them on rangers yet...

 

All 2007 Rangers have a TPMS that lights a warning light for low pressure.

 

good to know Bob thanks for the info.. something good to know.

 

how much work would it be to add this to an older ranger? (02 Edge)

*edit for spelling*