Tyre pressure confusion

Technical Area Wheels, Tyres & Brakes
1
  1. My model of MX-5 is: __ND3
  2. I’m based near: __
  3. I’m looking for technical help or recommendations on: __Tyre pressure monitoring

Could someone help me make sense of this… Supervisor went off to work this morning, 5 minutes later came back saying there is a tyre pressure warning. So, I check the vehicle status info that gives pressures, and each tyre is reading 180, as you’d expect on a cold morning, but the front right is illuminated with a warning, repeated on dashboard. Ctrl-Alt-Del car, warning still there.

I tell her not to worry and check later. This is what it now says…

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Pressures as you would expect, sun to the right warming the tyres, but still the unfathomable warning and not sure how to make it go away. :zany_face:

2

I’d be expecting 2.0, or 200 (29PSI). I’d check first with a physical pressure gauge.

Normally driving the car would be expected to clear any warning if there isn’t an actual issue.

3

Yes, I topped up to 200 in Dec, so you’re right, they do need another pump. I would expect those numbers (registers in increments of +/-10) but confused as to why it tells me there is a problem on the right wheel when it has more pressure than the left and the same as the rear. A 10 min drive didn’t clear the error, the sensors give live readings. I’ll pump up to 200 tonight and see what happens.

Stupid software error, I suspect. We just had to have a software update for the headlights. :woozy_face:

4

Does it have a reset option? My ND1 (no actual sensors in the wheel) threw up a tyre pressure fault, loss of pressure on OS rear, after a check it was ok. I reset the system and it’s been fine.

5

I asked Claude (AI assistant) and it came up with possible issues with the battery in the TPMS sensor and/or a communication issue between the sensor and receiver. It provided this supporting link to the MX-5 owner’s manual: Mazda MX-5 Owner’s Manual

6

No reset option, it’s a live pressure sensor, unlike those systems that measure the wheel diamater as it rotates and need calibrating when you pump up. The sesnsors seem to be giving the correct reading, it’s the way the daft computer is interpreting the result that seems odd.

7

My interpretation (maybe incorrectly) is that it’s telling you that there is a sensor problem, not a pressure problem.

8

Error message disappeared of it’s own accord.

Used a plug on guage to test, readings were just as sensors reported.

If there’s one thing I learned in a 35 year IT carreer, “Never attribute to hardware failure that which can be explained by software failure.”

9

Or can be cleared by a restart… also an IT veteran :wink:

10

Thanks for this topic! I did not know where to check! My tyres were too high!

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I will sort this tomorrow! I know 29 psi is recommended and don’t know why the local garage mechanic recommends 32 psi!

Ofiaich :grin:

11

He might be right. It also depends on other factors: tyre type, climate, altitude, driver and passenger weight, and driving style. Take 29 as rule for 1 Japanese sized driver, empty trunk, sea level, Hiroshima climate 70’F.