just wanna confirm if i have got tpm or ftm on my wheels cos the last time i checked the air pressure it was quite low so i wonder why the hell i didnt get any warning on the idrive if i had tpm, but then if i dont have tpm then why do i not get any error message either. the car is 57reg Lci so i believe it should have tpms but then again i dont get any warning for low pressure.

 

I'm pretty sure you have FTm as thats what i have inmy lci.The warning has only ever gone off once for me and that was about 6psi out.

 

What does "57reg lci" mean?

I believe BMW switched from FTM to TPM in 2007. My 2006 M5 has FTM which bascially are sensors that detect differences in wheel spin etc and will alert you if one of the tires seem out of sync with the others but it won't tell you which wheel. You'd have to go physically check them. The TPM in 2007+ cars have individual TPM sensors (TPMS) so the system will tell you exactly which wheel is flat.

Not sure why you wouldn't get a warning whether you have FTM or TPM. Should have your system checked.

 

Well, if you have FTM and it wasn't reset at the proper pressure then you may not get a warning if it's low on air. After filling the tires to the proper pressure go into the iDrive and reset the system to account for the desired pressure and you should get a warning next time it drops below a certain threshold.
What should concern you more is that the tire was very low on air to begin with.

 

sorry 57reg means late 2007

 

usually in the U.S. the ftm sensors have the black/plastic valve stems and tpm sensors have the metal valve stems.

 

As far as I am aware,FTM will inform you if one tyre pressure is not correct.However,if ALL your tyres are low,FTM will not give a warning.The procedure is for you to set all pressures correctly and then carry out the iDrive selection for FTM to go through an initialization process (a few miles of driving) before iDrive informs you that FTM is active.My model is pre-LCi and has FTM;a relative has an LCi model which also has FTM.Both models have 19" M172's with non -run flat tyres.

 

so basically its the system in the i drive rather then the sensors on the wheels, for example if i have got ftm system in the idrive and put tpm on the wheels, they just wont work. correct me if i am wrong. and tooltec as you say that ftm only warn me if one of the tire has a low air pressure but wont warn me if they all go low. but whats the possibility of all the tires going low at the same time ?. very rare i believe but again you guys are experts and i trust you.

 

FTM works by monitoring wheel revolutions (via the ABS sensors I believe) so it will inform you by iDrive if a tyre has low pressure because that wheel will have more revs/mile than the others.Look in iDrive vehicle settings, if you have FTM you will find it.Obviously,FTM is a safety warning that you have a slow puncture,if you have a tyre blow-out you don't need iDrive to tell you.It is not intended to tell you that your pressures are correct, it requires you to set them correctly and then go through the initialization procedure.As you say,if you don't have TPM on your car,then TPM sensors will not work.

 

I think i 've got FTMs in the car but what concering me now is that i am upgrading the wheels in next couple of days from 18" to 19" and someones coming over to do mobile fitting the tyres on 19" wheels, so my question is if i have got FTMs do i need to have something that goes with the new wheels like in case of TPMs you have to have new sensors or working sensors on the previous wheels. please let me know asap as i dont want to pay call out charge if the fitter tells me at the last minute that i dont have certain part that goes with the wheels so the i-drive doesnt give any errors. your quick help is highly appreciated. thanks