alaga

Something today that just popped up: twice while on a daytrip (250-ish miles round) the i-Mid displayed the "CHECK TIRE PRESSURE" warning. First time was about 80 miles out of town. I stopped and checked pressure. No loss of air, fronts were 34, backs 32. I put the fronts to 32, then ran the TPMS calibration - warning went away.

Then just before getting home, it came back on. Checked pressure again - 32 all around. Again did the calibration, although I was less than a mile from home.

This is the first time it's occurred, apart from when there was a reason (had the doughnut on while getting a bad wheel replaced). I'd made no changes to tire pressure in the last week - even made a little trip last Saturday without this happening.

Several 'stupid' questions, since they don't seem to be addressed elsewhere:

Does the calibration have to be engaged with the tires at cold pressure (in this case, 30)?

It requires 30 minutes of cumulative driving at 30-60 MPH. I'm guessing this would mean the calibration 'pauses' whenever speed is outside those numbers, or if the car is turned off less than 30 minutes later? Or is it aborted, and has to be restarted?

After engage, does the car have to be standing still for any length of time prior to moving?

Given the nature of this system, is there anything external I might have encountered which triggered these false readings, making this a fluke? (I read somewhere that something in the Bluetooth connection can trip it.)

ezone

It should be done this way, but it's not always possible.


Also, think about the temperature difference between middle of the night and middle of the day in your area. That alone might be enough to trigger a warning.

I assume you already read about driving on loose surfaces can trip the warning?
Did you notice the part about a heavy load in the car can also trip the warning?


KEY WORD: cumulative
In the shop we hit the reset then shut the car off or turn the car over to the customer. It will learn as they drive.
Nobody can realistically be expected to drive that long in one shot just to reset a tire light, it's not practical.


Should not need to. See above.


Ideally you should do the initialization on flat level ground, with the steering wheel pointing straight ahead.

No, there is no wireless anything involved in the newest system (indirect monitoring). The system now uses all the sensors that were already in the VSA system.



If the system turns the idiot warnings on, you must make some sort of change to the tires...
If you simply try to reset the system without correcting whatever the system thinks is wrong, it will turn the warnings on again very soon.
No, the system will not tell you what it thinks is wrong.
(don't feel bad, it doesn't tell us either!)

I dislike this system, there isn't an easy way to fool it. Every time the temp drops a lot we have a pile of customers come in with that dang light on, and usually we find the tires are aired to spec or higher.

ezone

Go to your dealer service department (hopefully with the light on) and have them update the TPMS/VSA system software.

Explain your situation if they ask, your warning comes on yet the tire pressures are all in spec.

Bulletin 14-042 addresses this issue, software update is supposed to make the system less sensitive.

ezone

The bulletin applies to 14m.y. only.

You may need to get vocal and request the software update (don't just go in and say your warning came on), as I can sure picture someone just airing up the tires and resetting the light like so many others get.

I know I don't always remember all the different bulletins and updates without looking, just like I did not remember this one until after I typed out the first reply.

I'd expect the update to take at least a half hour, so you should know if they just aired the tires and sent it out.

alaga

No unpaved roads this trip, and no unusually heavy loads (wife was with me in the car, but she was also with me the last couple of trips, and the TPMS didn't trigger).

The only change I made the first time it went off was to bleed a couple of PSI off the front tires to bring them in line with the rear (32). It was another 120 or so miles before getting home, when it went off again. Again, this false alarm hasn't happened before in 3,000 miles of driving.

Am now wondering if the system didn't detect enough of a change in the tire, hence the second warning -- should I have maybe dropped the pressure a good 5+ PSI, then re-aired it up for it to "see" the change? Also, does even bleeding the tire require a reset? I did change the pressure on a couple of the tires a week ago. But in city driving the past week it didn't trip.)

This is insane ... left uncorrected, it's a 'cries wolf' thing. I'll get jaded, then I won't take it seriously if I'm actually losing air.

Car is a 2014, and in service prior to the this TSB. At some point, I'll take it in and hope for the best.

jordan1794

Do you know what your cold tire pressure is?

If I remember correctly the warm tire pressure (At least, in my 2006 when I still had it) was close to around 34-36 PSI.

If the tires act similarly, you might be keeping the tires under-inflated enough to set off the sensor if you are at 32 PSI when warm.

Just an idea though, I'll try to check my warm tire pressure the next time I drive (I also have a 2014 civic)

EDIT: A quick google seems to point at a 10%-20% increase in PSI after 20 minutes of driving, which is perfectly in line with my 2006's 34-36 PSI when warm.
This would theoretically place, and a LOT of assumptions here so try to check yourself, your cold PSI is somewhere around 27-29 PSI.

The lower end of that range would probably set the sensor off. Not sure how finicky it is.

alaga

Number on the door jamb is 30 (odd, since most every other car I've owned specified 32). They were all at 30 the next morning.

Also, both times it went off were after many miles of interstate driving. If anything, as high as the tires would get.

ezone

The system would need to learn this new pressure first (reset+driving), you can't just air them up and let the air back out or vise-versa (effectively nil change).

The system has to learn a tire profile (how it acts while driving).
There is no pressure sensor anymore, thus no way for it to read actual pressure inside the tire.
ANY change requires a system reset/relearn. If it did not set the warning off, you're lucky.

If I forget to do a reset after rotating a set of tires, the car usually comes back in 20 minutes later with the darn warnings on.


I LOL'd

This bulletin says it applies to all 2014 Civics. (There are other bulletins to address other models with software updates for the same problem too.)

Software updates are released all the time for fixing (sometimes rather strange) issues, much older cars are often affected too.

When you have millions of lines of code used to run a car, there's bound to be occasional bugs (I guess 'bugs' is a good word for it), and these updates are how the manufacturer addresses bugs.
There's other stuff that can be addressed through software changes too.

Get it to the dealer ASAP and get the software update done (as per the bulletin number I posted earlier), then see how it goes.

It has reduced the number of complaints here.

HTH

pnamajck

good thread … thanks.