Flat Tire monitoring system

whatheheck · 1st September 2012, 18:15

Question please:

On my 2006 M6 - BMW's ancient design used technology that measures rotation of the wheel to sense when we have a flat tire.

Problem with this design is two fold. There is no visible air pressure reading available, and also a Flat Tire monitoring system is a poor design as it is basically a dead person monitor. It only tells you when you already have a flat tire / person is already dad. Too late.

We want a system that warns us if we are losing tire air pressure and also the ability to read tire air pressure and tire temperature on command. So a Tire Pressure monitoring system is a better design.

That is the reason I installed a Hella TPMS on my 2006 M6. The Hella design replaces the stock air valve with one that reads and transmits air pressure reading and also temperature reading. Data is sent to a display installed inside the cabin.

See here: Installation of Hella TC-400 Tire Pressure Monitor System

My question is on LCI models 2009 and on (as I just bought a 2009 M6 Cabrio). Does your 2009 or 2010 LCI models still uses Flat Tire Monitor System or did BMW finally installed wheel air valves that sends air pressure reading that we can read on the Nav display inside the cabin?

Thanks in advance.

zerocks1 · 1st September 2012, 19:39

Dan, I don't believe the following has changed in an 09> MY. Your 06 had an FTM (flat tire monitoring system) which merely measured pressure in each tire against an algorithm in a module to alert the driver when any tire drops below a pre determined set threshold (which can be changed via coding)

The 07> models have a TPM (tire pressure monitoring system). The name is misleading as the system does not send the actual tire pressure to a display, but rather sends the measured tire pressure to a newer type module that has a different algorithm, which compares each tire pressure to each other from the moment you reset the TPM in the iDrive (usually when you check or change air pressure, done manually by you). If any tire changes pressure vs. the other tires by more than the preset amount (also changeable via coding), the iDrive and cluster indicator will display an error

Unfortunately the actual tire pressure is not displayed. Like you, I have the Hella system and plan to add the sensors in addition to the OEM sensors next time I need tires. I plan to mount them 180 degrees opposite location from the OEM sensors using a hose clamp type mounting system, which I already have from my HRE wheels. They currently hold the OEM sensors.

Let newer model year owners weigh in on anything different

Happy Labor Day

SilberGrauE60 · 2nd September 2012, 04:53

Actually, FTM does not measure tire pressure. Instead, it uses the ABS sensors to measure tire rotation speed to tell if a tire has gone down. When a tire loses air, it's circumference decreases and thus spins faster to cover the same distance as the tires with the larger circumferences (full of air). The system is actually quite precise. I had a tire go down about 3-4 psi due to a nail in the tread and the FTM system alerted me. The only drawback is that it cannot tell you which tire has gone down, thus you need to use a tire gauge to measure all tires to see which has gone down. The big benefit is that it does not require the "expensive" TPM sensors in the wheels. If you change wheels/tires, all you need to do is re-calibrate so that the system knows the tire speeds for normal pressures.

Oh, and the '09 models have adopted TPMS (actual tire pressure monitoring) in place of FTM.

whatheheck · 2nd September 2012, 04:58

Thank you folks for the great info.

So I guess when its time for me to swap out my BBS rims from my 2006 M6 and move it over to my new 2009 M6 Cabrio FTM should work just fine because the 2009 Cabrio FTM system doesnt use tire air valves?

zerocks1 · 2nd September 2012, 05:01

Thanks SilberGrau, I had understood what you wrote as well until a BMW engineer who visited my dealership some years ago disputed that belief and explained it to me differently. He stated that the tire pressure monitors are basically all the same in all cars. Different designs, different frequencies. They all measure actual pressure. The cars electronics uses the info differently. Your explanation makes more sense. But whichever way it works, glad we answered Dan's question

Hasan Shaikh · 2nd September 2012, 09:25

WoW! Awesome info guys.

I have got to get me that Hella TPMS Dan had.

carrisco · 2nd September 2012, 09:43

Quote:

Originally Posted by whatheheck

Thank you folks for the great info.

So I guess when its time for me to swap out my BBS rims from my 2006 M6 and move it over to my new 2009 M6 Cabrio FTM should work just fine because the 2009 Cabrio FTM system doesnt use tire air valves?

Have you found a new M6? Or is this hypothetical planning?

-b.

Hasan Shaikh · 2nd September 2012, 09:46

Hi Bryan!

I think Dan has already purchased the car and is expecting delivery very soon.

Looking forward to the pics Dr. Dan.

carrisco · 2nd September 2012, 09:49

Quote:

Originally Posted by Hasan Shaikh

Hi Bryan!

I think Dan has already purchased the car and is expecting delivery very soon.

Looking forward to the pics Dr. Dan.

Why is he so secretive?

Maybe he was worried someone else would swipe it before the transaction was completed?

I hope he found the colors he wanted -- as I remember it, they were a bit unique.

-b.

Hasan Shaikh · 2nd September 2012, 09:53

Quote:

Originally Posted by carrisco

Why is he so secretive?

Maybe he was worried someone else would swipe it before the transaction was completed?

I hope he found the colors he wanted -- as I remember it, they were a bit unique.

-b.

Hahahaha!

I think he is just waiting to receive the car and the give it a nice lean and polish and then he will announce it with pictures and everything.

I am sure he has got what he was looking for. Otherwise, he would still be searching.