Tire Pressure Monitoring System (valve stem)

If you have a TPMS attached to the valve stems, when changing the tire, is there a wire attached to the inside of the wheel and connected to the stem, or can the tire be removed without worrying about damaging the TPMS?

Also, when buying new tires, does the tech need to reconnect any wires? Or does it work another way?

Assuming the sensor doesn’t fail, is it something that should work normally for the life of the car, or do the sensors have to be replaced each time you get a new tire? (They usually put new stems when you buy a set of tires, but I doubt those stems have any TPMS built in. Based on this, I assume they must work differently than I am picturing)

Thanks

There are no wires. The sensor is simply a small black box connected to the other end of the valve stem.

See here: http://www.ebay.co.uk/itm/4PCS-AUTEL-433MHZ-UNIVERSAL-TPMS-TIRE-PRESSURE-MONITOR-SYSTEM-SENSOR-DIAGNOSTIC-/181927372271?hash=item2a5bb765ef:g:Ao8AAOSwf-VWaEB3

There’s nothing special in the tire removal process, same as normal, non TPMS wheels. However rims must be marked and put back at the same position. If for example a front left wheel is installed at the rear right position, this could potentially confuse the on board computer.

TPMS sensors have a non-replaceable battery that will run out after 5 to 10 years. In that case the whole sensor has to be replaced.

No need to connect or disconnect wires for changing a tire or wheel.

Yeah, I have that issue on my 2006 Nissan. Just haven’t messed with it yet.

Just remember to always back up periodically, or the wires get all wound up.

Replace valves/TPMS sensors with new tire sets in order to maintain warranty support for the tires and sensors and avoid things like battery issues and potential damage during re-installation. Some shops and dealers have declined warranty support for TPMS issues after discovering the sensors are not theirs, or not OEM.

On the TPMS systems that keep track of which sensor goes to which wheel (many of them don’t) there’s usually a fairly simple procedure to re-learn which sensor is at which position. Otherwise tire rotations would become quite a lot more labor intensive!

My shop does that for me every time I take it in to replace the blinker fluid.

When you drive a car in reverse, does the odometer run backward? To keep the wires from getting all wound up, you would need to drive as many miles in reverse as forward, in the long run anyway, so you’d want your odometer to keep returning to zero. Also helpful to maintain your car’s near-new resale value!

yeah, and you can get TPMS “triggering” tools from pretty much any tool vendor, or even Tire Rack for some inexpensive ones.

That reminds me of when Bob Lutz was on The Colbert Report; when Colbert asked if the Chevy Volt’s 40 mile electric range meant the car had a 40-mile long extension cord. Lutz replied “We were going to include one, but people kept running 'em over.”

I all seriousness, no.

Years ago a friend and I rented a car for a long road trip. We exceeded the allowed milage by quite a bit. I came up with the (brilliant) idea to disconnect the speedometer cable from the transmission, and chuck it into a drill, which we then set to run backwards. The odometer backed up until the tenths digit was 0 and then stopped.

There’s a reason why that happened.

Less-than-honorable car sellers (many of them ‘Dealers’) found the ‘back-off-the-milage’ trick many years ago.

Laws were, IIRC, passed requiring odometers to be tamper-proof - at least for mechanical odometers.
Lord knows what a clever geek could do with an electronic display.

Well, they had this clever feature that you could wind back the first 50 miles or so!

So that the new-car dealers could reset the odometer to not show the shipping and delivery miles (and, in theory, so that you got full millage on your warranty).

But those dam sneaks in the press and consumer affairs got wind of this, and though it was misleading (or even … dishonest …) so that feature’s gone too.