Are newer tpms sensors movement activated?

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They can be depends on who makes them and the system.

It's also possible the car sends a signal and wakes them up when you start to drive.
 
Originally Posted By: i_hate_autofraud
It's also possible the car sends a signal and wakes them up when you start to drive.

Which means they would have to be constantly listening for the "wake up" signal, and that in itself would be chewing up their battery.
 
Listening to radio is usually less energy consuming than transmitting. So if “do not tell until asked” is implemented it may preserve battery life. Motion activation would be even better. I think engineers are using all the tricks available to save battery life.

Krzyś
 
They are in sleep mode. I believe the sensors are micro-machined electrical mechanical MEMS with on-board firmware signal conditioning. One of the features are nano current sleep mode. any movement of the device triggers the output. Output is nothing more than a bursted data packet. If the receiver is listening it will receive and decode the packet. They also go to sleep in between output pulses so the battery can last a couple of years.
 
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On my 2017 RX 350 you have to wait a few minutes after being underway before you can get a read from the TPMS which leads me to believe that they must be in sleep mode.
 
You may be thinking of ones that rely upon wheel speed differences instead of a pressure transducer.

My Honda Accord doesnt have any sensors in the wheel (fortunatelY). It uses an analysis of minute differences in wheel rotation.

Knock on wood, my BMW sensors still work.

Not sure what the lifetime of the batteries in these things are.

It would be sensible for the batteries to be isolated to avoid any quiescent drain.
 
Good question on the batteries in the TPMS system. 3 of the 4 sensors on my 10 year old Suburban are original and still work. One died and I ordered a package of 4 from Amazon. I gave one to the tire shop and they de-mounted the tire, installed the new sensor and activated it. I’ll do the other three when I toss these tires and buy new ones later this year.
 
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I've got to be moving in my Sonata for my tire pressure to display, maybe that's the same thing?
 
Years back, a hardware wireless application called "telepanel" had receivers and a CPU
that would 'wake up' and listen for 1 second and stay asleep 10 seconds and do it all
over again for years on 1 battery.

If there was an active data stream starting with a unit serial number, it would stay
on and turn off after data was received.
 
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