# New TPMS sensors or gamble with the old?



## m3_4_wifey (Jul 26, 2016)

I have a set of all season tires on back order that I'm going to have mounted in late April. Our car is a Model 3 LR that we got in the Fall of 2018. It took us about 3 seasons to go through the tires, but about 3.5 years in time.

TPMS sensors are suppose to last 5 to 10 years, so I'm wondering about reusing the TPMS sensors.
My gut is to go for it and use the old sensors with the new tires and cross my fingers that the batteries last.
Am I being foolish and I should get new TPMS sensors with every set of new tires? I would guess if the batteries do go, I'll be charged about $25 a tire or $80+ for the whole car. The cost and sourcing of the TPMS sensors is another topic.
If one goes it probably makes sense to swap out all 4 tires for new ones at the same time. The old battery smoke alarm problem.


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## TrevP (Oct 20, 2015)

You should be fine. The tire company can test it before they install.
You car uses the common TPMS sensor type (radio frequency) It's the new 2020+ Model Y and 2021+ Model 3s that use the new Tesla proprietary bluetooth TPMS sensors that are very expensive


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## m3_4_wifey (Jul 26, 2016)

Thanks Trevor. Ideally the TPMS sensors still have a strong signal.

It looks like it's possible to replace the batteries for some TPMS sensors. Not sure if it's possible to do with the ones a Tesla needs, but one option to buying new TPMS sensors.


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## garsh (Apr 4, 2016)

Worst-case scenario - a TPMS sensor stops working. The car will still function just fine. You'll just have to manually check air pressure periodically, just like the old days. Then once you've worn through the current tires, replace the TPMS sensors as well.


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## m3_4_wifey (Jul 26, 2016)

garsh said:


> Worst-case scenario - a TPMS sensor stops working. The car will still function just fine. You'll just have to manually check air pressure periodically, just like the old days. Then once you've worn through the current tires, replace the TPMS sensors as well.


Okay, good reminder that the car will only send out alarms for low tire pressure and not TPMS sensors that are not responding because the batteries are dead.


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## Power Surge (Jan 6, 2022)

m3_4_wifey said:


> Okay, good reminder that the car will only send out alarms for low tire pressure and not TPMS sensors that are not responding because the batteries are dead.


I've worked for both Goodyear and Firestone and know TPMS systems well. I don't know if Tesla's work differently, but every other vehicle on the road will definitely give you a tire light if a sensor is bad. Solid light on is low tire. Flashing light (only flashes the first few minutes of driving) is something wrong with the system (i.e. bad sensor). I don't see why Tesla's would be any different... it's a federal mandated system.

As for TPMS life, we start seeing sensor going bad around 6-8 years on the average. I would just use the ones you have until the first one goes bad. Then replace the set.


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## garsh (Apr 4, 2016)

m3_4_wifey said:


> Okay, good reminder that the car will only send out alarms for low tire pressure and not TPMS sensors that are not responding because the batteries are dead.


Oh, you'll get a warning message about a non-functioning TPMS sensor every time you drive the car, but you can safely ignore it.
In Pennsylvania, a functioning TPMS sensor is NOT required to pass inspection either. YMMV in other states.

When I had my NIssan Leaf, I had winter wheels/tires with no TPMS sensors. I just got used to the TPMS warning light always being on in the winter.

I also had a TPMS sensor go bad in my wife's Honda Odyssey. My solution in that case was to put a little piece of electrical tape over the TPMS warning light until I had the sensors replaced when it was finally time for new tires.


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## m3_4_wifey (Jul 26, 2016)

Here in Vermont a functioning TPMS is required for inspection, so there's a limited window of running the tires without working TPMS sensors.


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