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edrikk
07-28-2009, 09:50 PM
Hi guys,

I know many people have replaced their run flat tires with "conventional" tires. I was looking at Tirerack.com, and it mentions TPMS (Tire Pressure Monitoring Sensor), and they charge about $180 (as I recall) for them. Now, I understand why that is needed for the runflats, but is the sensor neccessary if I will buy conventional tires?

What happens (ie to the dash-light) if you put on conventional tires and no tpms? is the light always going to stay on?


I haven't taken ownership of my car yet, so please excuse me if this is in the manual somewhere.

A search of the forums didn't really provide an answer.

Thanks in advance!

Stephanie
08-06-2009, 08:58 AM
edrikk,

i had a friend that put winter tires on his existing rims without a TPMS... the stupid red light was always on on the dash, it was very obnoxious.

to the best of my knowledge, there is no way to reset the light on the dash (there normally is) because of the absence of the sensor.

Also, since the cars equipped with Runflats and TPMS no longer have spare tires, it is probably in your best interest to keep the TPMS in there in case you do get a flat, so you can take the necessary steps to save your rims before you drive on the flat for too long...

I have the 19" Style 230s on my 335 and the tires on those wheels are like rubber bands, should my tire blow when i remove the runflats for a better tire (next season) I'm gonna wanna stop driving ASAP.

Although, if you are paying attention, im sure you can feel the flat... I just wouldn't want to take that chance....

brunp
08-06-2009, 01:54 PM
I assume TPMS sensors are within each individual wheel. So, for those without it, like myself, conventional tires work well. Right now though, I have a slow rear-right leak which the installer has to fix (haven't done it yet) and if it dips below 30 psi, then I get a flat tire monitor indicator, but it doesn't tell me which tire. So, I had to go out, check, pump it up and reset the indicator...

I also wonder if you can disable TPMS monitoring via the OBD II connector.

Paul

DINO K
08-08-2009, 06:20 PM
if you have the iDrive, set your tire pressure where you want it, drive around for a bit and jus "ok" the "set tire pressure" then it should be ok, but if you dont have the iDrive, im pretty sure the car will adapt to the new tires, if not the dealer can set it on the ecu.

edrikk
08-10-2009, 11:41 AM
edrikk,

i had a friend that put winter tires on his existing rims without a TPMS... the stupid red light was always on on the dash, it was very obnoxious.


Strange! Was their car a US import? After a bunch of research, I have found that apparently in the 2006 and up Canadian models, they actually don't use TPMS, but instead use a FTM system (based on rotational speed)...

Apparently, if the (stock) tires have TPMS, they'll have aluminum stem valves, whereas the "FTM" ones should have rubber stem valvles...



http://www.canadiandriver.com/ctc/blog/sedans/2009-bmw-328xi.htm

http://www.1addicts.com/forums/showthread.php?t=241286

DINO K
08-10-2009, 11:50 AM
Strange! Was their car a US import? After a bunch of research, I have found that apparently in the 2006 and up Canadian models, they actually don't use TPMS, but instead use a FTM system (based on rotational speed)...

Apparently, if the (stock) tires have TPMS, they'll have aluminum stem valves, whereas the "FTM" ones should have rubber stem valvles...



http://www.canadiandriver.com/ctc/blog/sedans/2009-bmw-328xi.htm

http://www.1addicts.com/forums/showthread.php?t=241286

That's abs correct, and also on the iDrive the "set tire pressure" is under the FTM option

Stephanie
08-10-2009, 03:35 PM
Strange! Was their car a US import? After a bunch of research, I have found that apparently in the 2006 and up Canadian models, they actually don't use TPMS, but instead use a FTM system (based on rotational speed)...

Apparently, if the (stock) tires have TPMS, they'll have aluminum stem valves, whereas the "FTM" ones should have rubber stem valvles...

it was a 6-series... perhaps that made a difference?

ctgazer
08-11-2009, 08:45 AM
correct. 6-series use TPMS. 3-series are still on the FTM technology (this is ONLY FOR CANADIAN SPEC). i know this because only tpms is on my oem wheels. my winters dont have any as do my track setup. no lights, no errors.

US 3-ers are using the TPMS already

brunp
08-11-2009, 09:25 AM
Strange! Was their car a US import? After a bunch of research, I have found that apparently in the 2006 and up Canadian models, they actually don't use TPMS, but instead use a FTM system (based on rotational speed)...

Apparently, if the (stock) tires have TPMS, they'll have aluminum stem valves, whereas the "FTM" ones should have rubber stem valvles...



http://www.canadiandriver.com/ctc/blog/sedans/2009-bmw-328xi.htm

http://www.1addicts.com/forums/showthread.php?t=241286

I must tell you, the flat-tire monitor system that is based on rotational speed is sensitive because it gets triggered on my car if an individual tire hits below 30 psi....

Paul

Stephanie
08-24-2009, 08:54 AM
I must tell you, the flat-tire monitor system that is based on rotational speed is sensitive because it gets triggered on my car if an individual tire hits below 30 psi....

Paul

I'm pretty sure that's the point...

mousecrab
09-10-2009, 08:22 PM
i'm searching info on tire sensor as i'm planning to get a set of snow (convention) ties for the x3 and thinking if i need to pay the extra $200 for the sensor. guess it is not necessary, right?

brunp
09-10-2009, 08:58 PM
i'm searching info on tire sensor as i'm planning to get a set of snow (convention) ties for the x3 and thinking if i need to pay the extra $200 for the sensor. guess it is not necessary, right?

don't think it is necessary. Besides, any new sensors would have to be registered with the system. Not sure what happens when you swap to a set without TPMS....

Paul