Xphstos

So the Check tire pressure came on in the car about two days ago and since has not turned off. I have taken it and checked the pressure in all four tires and adjusted accordingly. Adding air as required, 33 psi front and 32 back. However, the light still stays on. My questions is once you adjust the pressure do you need to reset the setting? or do you think I need to call the dealer and have them look at it? Any insight would be appreciated.

Hobbes

Check the spare in the trunk, which also has a sensor. Assuming all the tires are properly inflated, reset the TPMS setting in the MMI, which should take care of things. If this doesn't solve it then may you have a problem.

petebet

Go into your car settings on your tech, and go to tire pressure setting. Once you set your new tire pressures there it will turn off. I just had the same issue this week. Good luck

HoustonA5

Once you ensure the tires are at the correct pressure, you need to go into the Car menu > Tire option (can't remember the exact verbiage) and click "Store Current Tire Pressures"
This will reset and turn off the warning light.

tgdA4

This confused me too initially. Also it would be nice to see the actual tire pressures for each wheel via the MMI. Does anyone know if this technology exists in other vehicles?

~pino~

Other systems do allow you to see individual tire pressures.
Pity that the Audi MMI (USA version, not sure about other countries) does not.

With the ambient air getting cooler in the US, you will be seeing the tire pressure warning if you don't adjust tire pressures for the weather. And as mentioned, the warning stays on until you reset the system under the CAR category of MMI.

tgdA4

Ran into this warning recently on a cold night.

Xphstos

Thanks for the quick responses. I will reset the setting tonight once I get in the car.

HoustonA5

This system doesn't actually read the pressures; it detects changes in the wheel speed via the ABS system to detect a pressure change. It's advantageous when it comes to changing tires and such, but is disadvantageous as it doesn't show the exact pressure

http://en.wikipedia.org/wiki/Tire-pr...itoring_system

See the Indirect Tire Pressure entry

ChipB

HoustonA5 - the '09 A5 (and S5) use direct tire pressure monitoring, not indirect.