I know this is a hot topic, but I couldn't find a thread specific to my issue.

So I bought my car brand new. I have had issues with the low pressure light [the one that looks like (!)] ever since getting it. It comes on about every 3k miles or so. Well now it's doing it once a week and it's driving me crazy.

I have had 3 different sets of tires on it and it's the same thing with every set. And sometimes the tires have been a bit low, but sometimes they're completely fine as far as tire pressure goes. The most annoying thing is that when I fill the tires to the proper pressure, the light won't go off as it did in my 2010 Fit.

I got fed up and last week I called my dealership explaining the problem. Dude told me that in the 2015 model I HAVE to reset it MYSELF EVERY TIME it comes on. I find this very hard to believe. That seems ridiculous to me! So I called a second stealership and the woman I spoke to said it depends on whether or not I have hard or soft stems. She said soft resets automatically and hard has a menu on the dash screen that you have to do something with. FYI I have soft stems.

Can someone set me straight? I got brand new tires on today.. started driving down the road, and the light came on again already. What is happening?

My main questions are:
1. Is my car broken due to it coming on all the time and seemingly for no reason?
2. Shouldn't the (!) light go off on its own after normal pressure is restored??

Thank you ahead of time. Slowly losing sanity over this

 

As per page 102 in my owners manual states, (2017) your book may be different, but in the section for TPMS, it says anytime you inflate,rotate,,or change the pressure in tires the button under the steering wheel must be pressed until light on the dash flashes, then it takes approx. 30 minutes of driving to calibrate the sensors. I just make sure I do it before I go to town or such a trip. Hope this helps. Many cars seem to be the automatic type as you speak but ours/all Hondas? may not be. I actually like this because we can put as much or little pressure in the tires as we wish, when the auto type may illuminate with running elevated pressure.

 

 

Manual reset required.

 

Bingo! Well put sir.

 

The car came with an owners manual. As already suggested, the specific information you are looking for is in it.

There's more they don't tell you in there, such as if the low tire warning light comes on and you hit the reset button (or start calibration) without changing whatever the system decided was wrong (it cannot tell you what that is), the system can turn the warning light on again in a very short time.


The people who answer the phones in a dealer rarely have deep technical knowledge. Seems like most service writers are simply salespeople and order takers who parrot phrases they have heard without real understanding.


The first person you spoke with was correct. The second was incorrect, they had it backwards.
In their defense, the same basic systems can have so many variations between the different models and trim levels it isn't even funny. It's damn hard to remember which car has what placed where and which cars have what combinations of systems installed, and remember at least 37 different ways to reset the oil change reminders or tire lights.

 

TPMS is using ABS speed sensors so you'll have to calibrate it when rotating or changing air pressures. It's easy enough to do and it hasn't come on for me too often, usually with big temperature swings.

I actually think it's too slow to react. Got a flat and did not trigger for at least a mile since it's a passive system. Compared to the active system in my other vehicle, it's very slow to react. The upside it's easier to deal with changing rims/tires and tire service is cheaper since there is not a TPMS valve stem to deal with.

 

Anytime that either the tire pressure is adjusted, tires are rotated and/or tires are replaced the TPMS must be re-calibrated. Like 2Rismo2 mentioned, this is a system that uses ABS/wheel speed sensors to monitor tire pressure.

It is indeed a very simple system to use once understood. Set the tire pressure to spec while the tires are cold, press and hold the tire pressure monitoring system reset button until the light flashes twice, then drive away (optional but I would recommend it). If memory serves me right, the system takes either about 10 miles of constant driving OR 30 to 45 minutes of accumulated driving to complete the learning procedure.

Please note that there is a preset threshold that triggers the tire light to come on. So excessive over or under inflation may cause the light to come on still. Tires with drastic differences (like 3 tires at 3/32nds tread depth and 1 tire at 10/32nds) can also cause the tire light to come on.

 

Wow, I just fell in love with my Fit all over again!!! I did not know the fits as well as some of the other new Hondas were of the indirect/abs type. I so despise the direct type in the tire, So glad to see Honda go with this! If I'm not mistaken, I think this is how tire pressure monitoring got its start in the later 80s early 90s, can't remember the car... porsche maybe, but this was when it wasn't so much for safety but luxury probably to know your tire was low from in the car.

 

That goes for crap on the wheel too ... I got the light one night last winter and was a bit nervous because it was not, um, optimal weather to change a flat. I checked the tires and saw I had a bunch of ice in one wheel so I chipped it out with a screwdriver and it was joyous days afterward.

 

The purpose of the learning cycle is for the car to learn the normal ratios of rolling radius of the four tires. They don't have to be identical in tread depth.

I also think that the system recalibrates itself gradually without pushing the button. My TPMS light came on once when the car was new and has never come on since despite the front tires wearing noticably more than the rears. I'm at the point of rotating front to rear at half treadlife and still no light. I'll bet that it will trigger after I rotate due to the abrupt change in ratios.

 

Actually drastic depth differences will cause TPMS errors to set. This is not a thought this is a proven FACT. This current TPMS system had gotten a lot of complaints from people who were still use to the prior system with tire pressure sensors... and still does.

The new indirect TPMS system monitors wheel speed side to side (Example: Driver front to Pass. Front), front and back (Example: driver front to driver rear), as well as diagonally (Example: driver front to passenger rear). All the tire/TPMS reset does is clear out soft codes, low tire codes in other words, as well as take note of the tire diameter. Mind you, just because the system does learn the tire diameter does not mean that it will also learn the tire diameter with a flat or low tire. The system will detect that flat or low tire and trigger a TPMS hard code that can only be cleared via scanner or hard reset if this is done frequently.

If the PCM sees that wheel speed to either too fast for its programmed threshold (since a low tire has a smaller rolling diameter, therefore will spin faster) the low tire light will illuminate. Having tires that are of the same size and are at similar tread depths on the same axles usually don't trigger a low tire DTC... again, provided that there is not a major difference in thread depth with the other axle.

SO for example... if you have tires at 5/32nds up front and 8/32nds in the rear, you may not see a low tire light illuminate since that may not a large enough of a diameter change for the PCM/TPMS module to see it as a low or flat tire. Now on the other hand, if the vehicle has two tires at 3/32nds on one axle or side of the vehicle and the other two tires at 10/32nds on the other axle or side, then that configuration may have enough of a difference to trigger a low tire/TPMS DTC due to the larger difference in rolling diameter.

Now finally, one way to FOR SURE have constant issues with the indirect TPMS system is to have one complete odd ball of a tire that is either at full tread with the others near the end of their service life at around 3/32nds from what I usually see OR the exact opposite, one tire at 3/32nds and the others at 8 or 9/32nds and higher.

 

Yep. Which again all comes down to the tire's diameter and how it affects the wheel speed sensor's readings.

 

I occasionally make a ~3 hour drive up to Chicago, and on three different occasions, my TPMS light has illuminated at roughly the same spot on the way back home. Scared me the first time, but after visually checking the tires, none looked low, so I drove on home where a check with my gauge showed they were all where they were expected to be.

All I can figure is that my route must have some sort of curve profile that's juuuuust enough to trigger the inside wheels showing as having rolled slightly less than the outside wheels. (c:

Really, though, no idea why it does this, and I ignore it now (reset when I come to a stop when I get off the interstate).

I do much prefer this type of TPMS. My ¾ ton pickup has the more common style and expects the fronts to be 65psi and rears at 80. Makes sense when I'm hauling a ton of hay in the bed and three on the trailer, but for riding around empty, it's ridiculous. Chrysler disabled the RAM dealer's ability to reprogram the thresholds, so I'm stuck either running super-high pressures, or living with a low pressure warning all the time.

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Isn't there a switch on the dash or a setting that you find in the gauge infometer to switch from towing tire pressure specs to empty tire pressure specs? I could have sworn one Ram 2500 I had at work had that feature...I don't remember what year or trim level.

 

Oh, I only wish! RAM HD forums are full of folks complaining about this "feature."

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