docfl

recently, the spare tire light came on, indicating loss of pressure.
both times the car had been parked outside for some time.
when i checked the pressure via the mmi, it was at 35 psi.
anyone have a similar problem?
Docfl
2004 A8L

buybeach

Oh, this is one of the many "issues" and "concerns" (read: failures) I had with my 2004 A8L.

I experienced one tire giving a false low reading. After a few days, this was followed by the entire system failing.

Audi knows all about this issue. I am surprised your dealer did not simply correct it.

You can turn the system "off" using MMI so you do not have to stare at the annoying flat-tire icon and have beep-tones come on at random times to warn you your tire is about to go flat while you wait for the very probably unavailable replacement part.

My car got fixed eventually by dealer replacing one of the antennas that work the system (apparently this is a radio-based interface).

GSR

I've had the problem once (with all four tires, not the spare). It was when we had an unusual cold day, as compared with the 90+ temps we've had for most of this summer. Since all of the tires were shown to be low, and at exactly the same pressure, I simply reset the calibration at that time. The pressure that is monitored is relative pressure, rather than absolute pressure. If the monitoring system was initialized at a time when the tire was warm (due to high ambient or driving), then it will generate a false signal when the temperature drops down. It may be the antenna problem that buybeach mentioned, or it may be that the system was improperly initialized.

Greg Elmassian

dumb question: spare tire monitored in 2002 a8?

docfl

What is dumb about the question?
Docfl.

Greg Elmassian

the fact no one answered it?