Hello E60 people, heres one for the forum. I just made a trip from ATL to NY and back last week. I had a blow out in the mountains of WV 500 miles from home. I put the donut on and limped 80 miles to the only tire shop opened in WV on Sundays with size 245 40 18 a NTB. I got the 1 tire left rear, and had the other 3 tires balanced and got a 4 wheel alignment. Driving the other 500 miles home the TPM system alarmed 3 more times with no flat tire present. I just kept resetting it and drove home in horror everytime it went off (no fun). It has been 4 days at home and it went off again today. I don't even know where to look because i'm not sure how the system functions. I'm sure you guys and gals will give me some knowledge as you always do! Thanks

 

Assuming we're talking about the 2004 530i from your sig, I believe you have Flat Tire Monitor (FTM), not Tire Pressure Monitoring System (TPMS). FTM works by comparing tire rotation speeds, not tire pressures. The theory is if a tire goes flat, its circumference is reduced and therefore it must spin faster than the one on the other side in order to cover the same distance. The difference in rotating speeds triggers the FTM warning. Pressure differences as little as 5-10 psi between tires will trigger the warning.

Now, you didn't say whether you were able to replace the bad tire with one with the identical specs as the original, but if not, this may be the source of your repeated FTM alarms. I do not know if the FTM system is capable of working correctly if two fronts or two rears are not the same size side-to-side.

The other thing could be that you did not initialize the system correctly upon replacing the bad tire. You must select "initialize" from the FTM page in iDrive, then drive off while the screen says "initializing" Eventually, it will switch to "monitoring" or something like that when the system is reset.

 

Sound like you hit the nail right on the head. I do have the FTM system and I only bought 1 new tire to get me home. They only had a tire called "Triangle" in that size so beggars could not be choosers when I was 500 miles from home. I was planning on getting a set of 4's in about a month anyways so I guess I'm going to have to bit the bullet on get them early. Thanks for the info.

 

Yeah if you have had the other 3 on there a long time and they are worn out, and you put 1 new tire on, the circumference will be different and you will continue to get Flat tire errors regardless or the Air pressure level.

This is one of the reasons the Gov mandated the TPSM systems instead of the cheaper ABS based wheel speed sensors the car companies wanted(but then you can run in to radio interference and they tend to be sensitive enough to pick up a 2-3 psi difference....can't win them all )

 

I have na 2008 528i that gives false tire location all the time. As usual BMW could not duplicate the problem. I had to eat a new tire because I received a low pressure alarm on the LF tire that could not be reset. Before I could get to BMW the right tire went into a major alarm as it melted down onto the rim. Anyone have ticking(ie lifter noise? ) thanks.

 

YIKES - were you not aware there was a tire problem until it "melted down" ... Were they RFTs or conventional?

BTW, I find that pictures are very helpful - if your cell has a camera take a pic of warnings that come up in iDrive. That way, in event they are not recorded by any of the on-board computers you'll have some evidence to show your dealer. And if your dealer can't diagnose that kind of a problem I suggest you consider moving the warranty work to another BMW store.