Talk:Tire pressure monitoring system

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First, a question:

What frequency do these TPMS's operate at?

Answer: Frequency of operation depends on the regulations of the communications authorities in each country, but is generally restricted to bands used for "low power short range" communication, i.e., 315 MHz and 433 MHz —Preceding unsigned comment added by 58.167.83.211 (talk • contribs)

Second, a warning:

I have been told by VisiTyre that RF type TPMS's can be interfered with by the automotive's components such as the axles, brakes and rotors, etc. Can anybody collaborate with this?

209.74.13.157 14:36, 5 April 2007 (UTC)

US DOT NHTSA acknowledges that up to 1 percent of replacement tires make battery powered Radio Frequency based tire pressure systems inoperative (or 2.25 million of the 225 million replacement tires sold annually in the United States). This is due to the ferrous and carbon black content in the tires which causes them to shield the RF energy, much like a Faraday Cage.
Reports are also being made that some RF based TPMS take more than 20 minutes to register tire under-inflation because the vehicle geometry and metal components block or attenuate the low power signal's "radio path" to the receiver electronics.—Preceding unsigned comment added by 58.167.83.211 (talk • contribs)

[edit] QUESTION:

Who are the experts in the tire pressure monitoring industry? I'm doing some market research on the industry. Thanks in advance for the help. —Preceding unsigned comment added by 76.230.117.206 (talk • contribs)

[edit] External links

This entire section had been given over to inappropriate links, so I have removed it. Please review WP:EL for policy on links to external websites, thanks. — BillC talk 14:13, 17 February 2008 (UTC)

[edit] Security discussion

The security discussion seems far from being a hoax. Here is more information I found that at least partially corroborates the security argument:

These links verify much of the security data, including details as to how each individual tire is identified and registered.

This clearly allows for someone to specifically register our cars for identification even if the car companies aren't bothering to track serial numbers (and why would they since they are likely just pulled out of a bin and the car learns the numbers dynamically). All you would need to do is stand next to the car you wanted to identify and read the signals coming from the tires to get a "signature" for that car. The newer sensors with accelerometers can be set to only be on when the tires are rotating at a certain rate. This would make the process of "learning" a person's car more difficult, but not impossible.

So, while some of the particulars (the doom saying, specifically) may be wrong, the base information seems valid, so he may be incorrect about it happening, but the possibility is not a myth. Does the low likelihood of an event's occurring mean it should't be listed on the article? - S. Gartner talk 00:46, 2 April 2008 (UTC)

The worst thing is the possibility for assassination use. The sensor emits radio signal, so the car's proximity to a road-side IED can be detected with high precision, allowing for most effectively timed explosion. Other "benefit" is the unique ID emitted by the TPMS sensor allows for singling out the victim's vehicle, so the IED can be left at the planned scene without any human supervison, as it will not go off at random passer-by car, just the pre-selected target vehicle.
Assassination by bombing cars on the road is quite common in Iraq. Italian investigative judge Falcone was blown up by the maffia using a half ton of TNT hidden under the autobahn, the godfather personally pressed the big red button. The top german banker was also killed in his armoured car in 1989, using a photosensor-triggered shaped charge device (obvious secret sevice kind of job). The use of simple and cheap "made in china" TMPS-sensing radio chips would make these kinds of assassination methods straighforward and available for the masses, not just the wealthy and resourceful and thus nobody would be safe on the road anymore.
Shall I mention pakistani military dictator Pervert Mustafa has already survived three massive IED bombings against his motorcade, including one where a bridge was blown up, solely because of two crates of high-tech jammer kit installed in his car by his US allies. 82.131.210.162 (talk) 09:00, 2 April 2008 (UTC)

The very low power output of the RF signal on direct TPMS sensors would require a following vehicle to be within a few feet of the target vehicle.

Removed tons of citation needed claims since all of them are covered by the reference at the end of the paragraph. User:Teutonic Tamer could have read that before spending so much time inserting faulty citation needed markers. If the referenced document itself is disputed, come here and let us know what is wrong about it, but claiming that something isn't a reference when in fact it is, is like saying the bible doesn't mention God. Trivial to disprove. --lynX (talk) 14:47, 9 April 2008 (UTC)

This Subaru website states that the sensors only transmit about once every minute. If the low power signal is detectable 50 feet away, it would take 105.6 sensors every mile to keep track of my car. It would be more efficient to observe the make, model, and plate number of the target vehicle and follow at a discreet distance. No tinfoil hats or black helicopters are needed. --Tarantulas (talk) 22:39, 11 April 2008 (UTC)

All sensors respond exactly within a specified time frame. Some of them respond within miliseconds of activation. The trick is to generate the proper Low Frequency (LF) datagram required to activate the sensor. A continuous wave Schrader style OEM part requires a large amount of LF in a continuous wave for several seconds, while the Ford Corporate or Chrysler Corporate sensors respond within miliseconds of activation. Anyone with an oscilloscope, can reverse engineer the activation tools on the market to determine what will wake up each sensor type. Detectible distance is relitive to background noise. Most TPM's transmit many frames of data making it easy to filter out background. Many TPM's can be activated, read and detected from hundreds of feet away. —Preceding unsigned comment added by 69.212.36.88 (talk) 13:16, 6 May 2008 (UTC)