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      11-20-2012, 09:33 PM   #35
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Drives: 340i M-sport AT
Join Date: Mar 2006
Location: Chicago

iTrader: (1)

Originally Posted by SamE30 View Post
Also, keep in mind FTM and TPMS are two different things in the BMW world.

TPMS was mandated in the US after the Ford Exploder incident. It utilizes sensors in the wheel itself.

FTM uses your wheel speed sensors to detect a flat tire, it won't actually be triggered until about a 6psi difference from the initialization pouint. It's pretty simple actually, a tire with less air in it has a smaller diameter, thus it spins faster. I know the Canadian spec BMW's use FTM, not sure if the US car's switch to FTM, or they sttill use the TPMS system. I haven't seen a US spec car in a while.
Good to know. I wasn't aware that in Canada your cars don't use TPMS as standard. FTM costs less and customers don't have to worry about the tire sensors when mounting different tires.

US cars have to have TPMS, so no need for FTM, as TPMS actually measures each tires individual PSI.
There are air pressure sensors in each tire that transmit their pressures to a central receiver that then communicates with the cars computer.
I think TPMS is a better way to do it, although it costs more for the manufacturer and the customer.

US F30's have the capability to show each tires pressure, but you have to code it to get the reading.
A member on here, SVACHE, has the codes if anyone is interested in turning on that function. I have no idea why BMW didn't just turn it on by default, after all it's already in there, just not turned on.

A reset of either system is still a good suggestion to at least eliminate that potential as the issue.