I looked up and down the Z4 forum, so I hope this isn't a repost:

My run flat alarm light just went off... I've listened to each tire and inspected them visually, but cannot find anything that would indicate a flat. All tires look fully inflated (and tire pressure is almost identical on each tire).

Is this a common problem? Any suggestions on how to verify when the little light comes on that it's an actual puncture?

Thanks, All.

J

I looked up and down the Z4 forum, so I hope this isn't a repost:

My run flat alarm light just went off... I've listened to each tire and inspected them visually, but cannot find anything that would indicate a flat. All tires look fully inflated (and tire pressure is almost identical on each tire).

Is this a common problem? Any suggestions on how to verify when the little light comes on that it's an actual puncture?

Thanks, All.

J

I haven't had a false alarm, but I did have and actual flat tire. I would suggest filling all the tires, resetting the indicator (I forget the procedure, but it's in the abreviated owner's manuel). If it comes on again, check all the tires to see if any are lower.

There's a good chance it was a false signal (I'm not sure exactly how the sensors work or what would set them off, but I'd expect it could happen).

Welcome to the world of owning a new(er) technology and a European car...
I remember the old Audi I had with the first version of ABS-- downright dangerous.

Have you fitted non-runflat tires to the vehicle...

I saw an X5 with runflats- sure goffed up the rim well!

From what I understand, there are two types of flat tire sensors. First type are attached to the valve stems and measure actual tire pressure. Second type monitors tire revolutions and compares between wheels. IE, if one tire is rotating at a significantly different rate than the others, it means there's a big tire pressure difference. The Z4 has the second type of sensors, so it does tell you if there's a flat, but it also tells you if there is a significant difference in air pressure between tires. You're saying there was no major difference in the tire pressures, so it sounds like it might have been a false alarm. If so, double check the tire pressures to be sure, then when you first start the car and before you move, push and hold the Tire Sensor button on the console until the warning light turns yellow. Then release the button and drive off. The sensors should recalibrate and the warning light will go off.

the tire moniter does not mean that it has to be a flat for it to go off. but rather the air pressure in one tire is lower than the other tires. i had mine go off once. pulled into a gas station to check the pressure found that one tire was off by 5psi-6 psi. upon more inspection i find that the tire has a puncture. so i fill up the tire reset the system and got the tire patched.