I had just left work about a week ago (no performance driving, just going home from work in a 45MPH zone) and suddenly the TPM (tire pressure monitor) lit up and said it malfunctioned, and to take it in for service. I hadn't hit any bumps or anything. I tried to reset the TPM but it just said "Resetting...." and never finished resetting. It normally finishes resetting within about 30 seconds or so, but this message remained.
Well, I pulled over and turned off the car, went in a shop and had a coffee to think about how I would arrange to have the servicing done to fit my work schedule. When I was finished and went and started the car, I decided to reset the TPM one more time and it reset and everything was fine. It's been a week and no issues.
I guess the computer just glitched or something. I remember with my 530i (2005) that the bluetooth occasionally would not boot correctly and in such cases it would not work until I would turn the car off, let it sit for a few minutes, then turn it back on and it would be fine. I figure it was the same kind of thing with the M5's TPM.
I hope your's is as simple a problem. If not, check the ABS sensor plugs at each wheel to make sure something didn't knock a sensor loose. I suspect since the DSC appears to be involved as well it might be an ABS sensor, or ABS sensor processing unit, since the car uses those for both TPM and DSC.
-Dave
LJMartin:
FYI, I haven't had a low pressure with my M5, but my E60 530i I had a couple (construction area around my house) and the TPM would typically inform me about a flat when the tire dropped to about 20 psi, which is 15psi below the recommended pressure I kept them at. I suspect that the M5 TPM would be about the same. Also, it doesn't say the tire is "low", it says something like "You have a flat! Pull over and stop the car carefully!" The first time I was like "Oh S**T, my wheel will be ruined." But after pulling over and looking it was hard to tell which tire was actually low. I had the Sport package with low profile tires.
