TPM Malfunction this morning
 

Hello all,

This morning I was driving to have the front brakes done and 5 miles before my arrival the TPM Malfunction light came on. The system was reset on the way home and seems like it worked but I just got a call from my wife that it just came on again. 2011 50i xdrive with runflats. We had some serious temps out there(110+ F) and I wonder if that has anything to do with it. I don't have a flat as the Indy shop checked the tire pressures and TPM Malfunction is directly related to the sensors... so not sure what to think before I call BMW. Any ideas?

Thanks.

It is probably a battery in some of the sensors going weak. unfortunately on E70 there is no recognition of the location of each sensor, the system needs to receive 4 signals and is good. Once one of the signals is lost the malfunction message comes up. i had an intermittent problem like that and it took me months to figure out which sensor is bad.

Appreciate the response bawareca. I will have to make sure that my tire pressures are good and see if the problem comes back again. It appears that the TPM message including the tire hazard icon went away after she stopped for gas at Costco. Strange....

Malfunction message has nothing to do with the pressures. Sometimes when you stop the signal of the troubled sensor is found again and the message may not come back for a long time. It is mostly random as per my experience.

About temperatures; the relationship is PV=nRT, the Ideal Gas Law, and T is absolute temperature, usually in °Kelvin where STP room temperature is about 300°K.

Pressure changes due to temperature changes, all else equal, are proportional to changes on that scale.

This has been discussed before, most E70 do show each tire status individually.

If you go to Pep Boys they have a device that can check the TPMS. It will tell you the status of the sensor and the battery charge.

When I asked them they checked them for free. No need to remove tires wheels or anything.

Will definitely do that today.

I am speechless about this. My wife's non-nav Z4 shows which tire is low, but my X5 doesnt :confused: I would like to meet the smart ass inventor of this :stickpoke

There are two systems, Tire Pressure Monitoring - TPM - and Flat Tire Monitoring - FTM.

TPM uses a signal from the tire mounted pressure monitor sender. Quoting from my X5 manual dated 2011: page 97 "Status indicator on the Control Display [ ... ] One wheel is yellow A flat tire or major drop in inflation pressure in the indicated tire. All wheels are yellow > A flat tire or major drop in inflation pressure in several tires.[my emphasis]"

TPM is Federally mandated.

FTM Flat Tire Monitor (page 94) "The concept [ ... ] It detects a pressure loss in a tire by comparing the rotational speeds of the individual wheels while moving."