The tyre pressure warning light is a very frequent occurrence, even though the pressures are OK.
Viewed a video on youtube.com and read the User Manual. Both advised that if the Tyre pressure reset button is pressed without adjusting the tyre pressures then the tyre pressure monitoring system cannot reset.
The tyre pressure monitoring system then may not give warning if a tyre pressure drops OR may give warning if the tyre pressures are OK.
I believe I have followed the advice by taking steps as described below, but still the tyre pressure warning comes up on a daily basis
1) I wait until the tyres are cold
2) I plug my compressor into the 12v Aux supply (yesteryears cig lighter plug).
3) Push the starter twice for accessories.
4) Let my tyre pressures down below recommended pressure to ensure definite changes in pressure of all four tyres.
5) Pump tyre pressures to recommended tyre pressure.
6) Push and hold the tyre pressure reset switch until the icon beeps once and flashes twice
7) Push the starter button to switch off the accessories.
8) Drive for say 15 miles and hey presto get the tyre pressure warning.
The same problem exists with our 2017 Mazda3 Sportnav, but the warning reoccurrence even more frequent than with our MX5ND.
Am losing the will to live here. Can anyone advise as to where I am going wrong?
While it is quite possible some MX-5’s have actual pressure sensors on the wheels, I have never actually seen any. So the “pressure” is being sensed by the ABS sensors looking for differing wheel RPM’s. As a tyre deflates its effective diameter decreases and so it will turn faster relative to the other wheels, assuming they are not deflating at the same rate. It is a very common system for checking tyre deflation.
Because of this deflating and reinflating should have zero bearing on the outcome as it is not actually measuring pressure.
There could be many causes for this problem.
Firstly and most conveniently would be a system fault or that the resolution on the software is just too small. You would need to speak to a Mazda dealer as it is nothing in the wheel.
Secondly you do actually have a puncture of some nature and the system is actually reading correctly.
You have a miss match of tyre diameters so one, or more, is actually worn, or new can causing a speed difference due to a diameter difference. In addition it could be just road layout locally to you accentuates in that the curvature of a particular road and the length of it works with the diameter difference to trigger the system. Tyre diameters will and do vary between manufactures.
You have a ABS fault such as, somehow a tooth on the sender ring is missing giving a spurious reading.
There is some other road condition that is causing the issue since you say it happens to your other car too.
I would suggest you need someone to read the diagnostics to tell you what exactly is happening.
Early NDs such as my 2015 car have indirect ABS sensor TPMS. I believe they have now switched to a direct system with sensors in the tyres. May have been 2018 model year that saw the change but lets wait for an expert to confirm this.
VIN serial number 200001 onwards, yes, I think May 2018 facelift, changed back to wheel units. 100001 serial number cars have indirect TPMS. I say back to wheel units as late NC (VIN 350001 IIRC) had wheel units.
ET, after resetting the system, the module learns the wheel speeds. Steering and braking actions hinder that learning process. After resetting the system, are you able to drive for a period of time at a steady speed and along a straight duel carridgeway? After a period of driving, if the system is unable to learn the wheels speeds it puts the light on to warn you that it hasn’t been able to learn. It sounds as if that is what is happening to your car.
When we bought our brand new Mazda3 just over a year ago just before we drove it away we were told by the sales person that the Tyre pressure warning light might come up and not to worry. At the time this didn’t worry us too much since our MX5 ND bought a year earlier exhibited this same trait.
All the technical points put forward by NickD are welcomed and well understood by myself BUT i can’t help feeling that there is some serious shortfall in the Mazda system that may possibly have been put right from 2018.
Mazda do advise that not adjusting tyre pressures before resetting the TPM may have a bearing on the outcome (If tyre pressures are not adjusted then may get no warning if pressures change or Warning if pressures do not change).
If there was any significant problem with an ABS toothed ring I would expect an ABS warning light.
Tyres can often wear at different rates on each corner, so this would be a significant shortcoming if wheel speeds are used to monitor tyre pressure leaks. Although were my MX5 ND is concerned I have been impressed with the suspension geometry set up in that the wear on the tyres on all four corners is so even. Any deviation in diameter of a tyre ( same manufacturer, type & spec) playing a part would be a significant flaw in the choice of a tpm system that uses wheel speed.
Our 2013 Seat Leon had exactly the same shortfall with tyre pressure monitoring. So Mazda’s system maybe common in many other makes of car.
Maybe cynical of me but a 70 mile round trip to my dealer (Within warranty on both vehicles) could prove fruitless. The experiences with our Seat Leon, our MX5 ND and the pre warning of the salesperson at collection of our Mazda3 does not fill me with confidence that this may be easily resolved.
Despite past negative experiences of diagnostics with vehicles of various make, the suggestion that diagnostics at the dealership may throw some light on this may reluctantly need to be followed up.
Our car had 3 false alarms in the first year spread out over several months. We have had none in the last two years. I suspect that the software may be the issue so I would ask for the latest software to be down loaded to the car to see if that cures it. If it is still under warranty then do go back to the dealer to get it noted and hopefully fixed.
When ours failed I just reset the system with the button on the dashboard, I did not adjust the pressures, it may be worth a try.
In our first year of ownership of the Mazda 3 and the first two years of the MX5 we only had a few false alarms.
It is only in recent months and weeks that the frequency of alarms have increased and particularly with the Mazda 3 are virtually a daily occurrence.
We usually reset the system with the dashboard button without adjusting the pressures.
It is only in recent days that we have followed Mazda’s recommendation to adjust pressures before reset of the system, but without success.
I also am led to believe that a change in tyre pressures evenly on each tyre (say due to significant ambient temp changes) may also bring up a warning.
Will in the coming days take Roadster Robbies approach and drive at a steady speed or along a straight duel carriageway after reseting the TPM system. If that fails I will certainly contact the Service dept of our dealership re software update.
The tire pressure monitoring system has a mis-use prevention logic which illuminates the tire pressure monitoring system warning light if the tire pressure monitoring system initialization is performed two times without adjusting the tire pressures even though the tire pressure monitoring system warning light was illuminated.
The data at the point in time that the tire pressure monitoring system warning light was illuminated is compared with the data at the point in time that the tire pressure monitoring system was initialized, and if the difference is within the specified value, the mis-use prevention logic detects and counts the number of detections.
If the detection is the first time, the tire pressure monitoring system warning light is not illuminated.
If the detection is the second time, the tire pressure monitoring system warning light is illuminated.
So if the system alarms twice and pressures are checked as correct and reset each time it will continue to alarm. The only way to then reset the system would be to alter tyre pressures to an incorrect pressure and reset, then drive for a while. Only then could the pressures be corrected and the system reset.
My system has brought up an alarm on one occasion, all pressures were correct. If I had been unlucky enough to get a second false alarm shortly after then I would have to run the car with incorrect and therefore unsafe pressures before the system could be successfully reset. Crazy.