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A couple years ago I picked up some Autel MX Sensors which support "cloning" through their diagnostic tool. Then I cloned my summer tire TPMS IDs to be the same TPMS IDs as my winter tires, and now I can swap them seasonally in only a few minutes with no need to make the car relearn them.
Yeah, TPMS and the way its implemented is a BAD idea.

1. Data is not signed.

So data can be easily spoofed and jam up the real sensor's transmissions.

2. Serial number is not obfuscated or in a reduced serial number set.

This allows TPMS trackers to be placed at high vehicle through areas and uniquely track cars. Is dying out due to Flock and ALPRs.

3. Some cars, primarily luxury, will force slow you down to 15mph, honk horns, and go into limp mode.

Note this is trusting unencrypted, unsigned, cleartext data. This is a terrible idea, and you cant turn it off.

> 3. Some cars, primarily luxury, will force slow you down to 15mph, honk horns, and go into limp mode.

Source? I can't find any reference. It looks like you're hallucinating.

TPMS is just another surveillance method. Check your pressure like the old days.
In the old days people didn’t check them and they’d run around on underinflated tires on the highway until they had a front end blowout and took out a family minivan in the neighboring lane.

That’s why it’s a FMVSS requirement now.

There are secure TPMS implementations, e.g. ABS sensor based systems.

TPMS is necessary if you have run flat tyres. Otherwise, I agree.
I'm surprised to not see any mention of indirect TPMS anywhere in these comments.

https://en.wikipedia.org/wiki/Tire-pressure_monitoring_syste...

It has its own shortcomings, but in my opinion they're all relatively minor and it does the job of warning the driver of potential pressure problems without wireless or in-tire sensors that require replacement.

EDIT, never mind, I wasn't seeing "indirect" in the comments but now that I look I do see "ABS", which is what iTPMS depends on for determining wheel speed.

I've got an RTL-SDR radio listening on 433Mhz near a public parking lot and I can definitely see the comings and goings of individual cars. While I'm sure ALPRs are taking over any TPMS-based surveillance there's definitely a risk there.

Aside: I'll never get another chance to share this, so please forgive the "humor".

Once my wife was driving, with me as her passenger when, the car's TPMS indicator came on. She was concerned and said "There's this 'TPMS' warning light here. What does that mean?".

Without even thinking I said "That probably means something." Likely the greatest accidental fitting of words to an initialism I've ever made in my life.

> I've got an RTL-SDR radio listening on 433Mhz near a public parking lot and I can definitely see the comings and goings of individual cars.

For anyone else looking to do the same with it this project is great: https://github.com/merbanan/rtl_433

One perfect example of why cars cost so much more these days. It was totally unnecessary, too.
I've had to replace two tires (and I don't drive very much) that would've been fine if I'd have noticed them going flat. But the first thing I noticed was the thumping and at that point they were badly damaged from driving them under inflated already.

There's a third incident like that too, but since I figured out that it had been flat when I started out, that I could've prevented it by looking at the tires (with a flashlight, cause it was dark).

Tire sensor component is a wireless component, calibrated to the dash.

A compression test for whether manual transmission engine is capable of cylinder combustion.