Tire Pressure Monitoring
Tire pressure monitoring system
Introduction
The tire pressure monitoring system monitors air pressure in all four road wheels and the spare tire while the vehicle is moving.
As soon as the tire pressure monitoring system senses a significant loss of air pressure in one or several tires, text messages and yellow symbols appear in the instrument cluster display to alert the driver.
The system continuously receives radio signals from sensors located inside each tire.
Be aware that tire pressure is also dependent on the temperature of the tire. For every 18°F (10°C) increase in tire temperature, tire pressure increases by about 1.5 psi (0.1 bar). The tire warms up while the vehicle is moving and tire pressure rises. So you should adjust tire pressure only when the tires are cold, when the temperature of the tires is roughly the same as the ambient air temperature.
The current temperatures and pressure of your tires can be viewed in the MMI.
You can find the tire pressure specified for your vehicle on the label located inside the fuel filler flap.
WARNING!
- When the tire pressure monitoring system warning light is lit, one or more of your tires is significantly under-inflated.
- You should stop and check your tires as soon as possible, and inflate them to the proper pressure as indicated on the vehicle's tire pressure label.
- Driving on a significantly under-inflated tire causes the tire to overheat and can lead to tire failure.
- Under-inflation also is likely to impair the vehicles handling and stopping ability.
- Do not adjust tire pressure when tire temperature is excessive. This could lead to serious tire damage and even cause the tire to burst, with the additional danger of an accident.
For the sake of the environment.
Driving with under-inflated tires reduces fuel efficiency and tire tread life.
Tips
- Each tire, including the spare, should be checked monthly when cold and set to the recommended inflation pressure as specified on the tire pressure label.
- The tire pressure monitoring system helps the driver to keep an eye on tire pressures. But the driver still has the responsibility for maintaining the correct tire pressure.
- Tire pressure must only be adjusted when the temperature of the tires is about the same as ambient air temperature.
- When tires are replaced, the sensors and valves should not be detached or exchanged. Only the valve core needs to be replaced and, if necessary, the valve and the wheel electronics replaced.
Significant loss of air pressure
The yellow symbol appears in the event of a significant loss of air pressure.
When the (!) warning light in the instrument cluster illuminates and then the low tire pressure symbol appears, this means the tire pressure is too low in one or several tires.
- Stop the vehicle.
- Inspect the tire or tires.
- Change the tire if necessary.
The (!) warning light in the instrument cluster illuminates when:
- the tire pressure is 7 psi (0.5 bar) lower than it should be.
- the tire pressure is 25% lower than what is specified on the tire pressure label.
- the tire pressure falls below 23 psi (1.6 bar).
Also, the low tire pressure symbol will appear together with the following message "Please check tire pressure".
After a few seconds, the message disappears again. If you would like to show the message again, press the "CHECK" button.
Tips
- In the case of an intentional loss of air pressure, for example, when re-adjusting tire pressure, this has to be stored again afterwards.
- Current information about tire pressures and temperatures can be scanned in MMI.
- The message in the event of loss of pressure in the spare tire is not activated until there is a difference in pressure of 7 psi (0.5 bar) from the specified pressure.
- Tire pressure must only be adjusted when the temperature of the tires is about the same as ambient air temperature.
Displaying tire pressures and temperatures
The current status of the tires can be displayed in MMI.
- Press the "CAR" function button.
- Select Systems in the CAR menu.
- Select Tire pressure monitoring.
- Select Display tire pressures. The tire pressures and temperatures are displayed.
Current tire pressures are shown in green and yellow numbers. The meaning of the colors is as follows:
- Green: If current tire pressure and the specified pressure are approximately the same, the tire pressure is shown in green.
- Yellow: If current tire pressure is more than 7 psi (0.5 bar) too low with respect to specified pressure, the tire pressure is shown in yellow.
Tips
- During the learning period, tire pressure and tire temperature are not displayed. Horizontal lines are displayed for pressure and temperature.
- You can find the recommended tire pressure for your vehicle on the sticker inside the fuel filler flap.
Storing tire pressures
Correct storage of specified pressure is the basic requirement for reliable tire pressure monitoring. In order for the tire pressure monitoring system to operate appropriately, you have to re-save the specified pressures whenever you adjust tire pressure, for example when the load condition of your vehicle changes. Proceed as follows:
Correcting tire pressure
- Check the pressure in the tires (including the spare tire).
- Adjust air pressure as needed in accordance with the information on the sticker inside the fuel door.
Saving tire pressures
- Press the "CAR" function button.
- Select Systems in the CAR menu.
- Select Tire pressure monitoring.
- Select Store curr. tire pressures.
Following each intentional change in specified pressures, tire pressures must be resaved.
After you have saved the tire pressures, the system will measure the actual pressures once again, and then save these as the new pressures.
Tips
You can find the recommended tire pressure for your vehicle on the sticker inside the fuel filler flap.
Changing a wheel
When you change a wheel, the new tire must be initialized.
- Press the "CAR" function button.
- Select Systems in the CAR menu.
- Select Tire pressure monitoring.
- Select Initialize wheels.
When you change a tire, you must perform the Initialize wheels procedure. You must do this each time to change a tire. The procedure can take up to 20 minutes. During this time, the tire pressure and temperature will not be displayed because the sensors are being "broken in" and the learning process is taking place.
During the learning process the tire pressure monitoring system is only partially available It only warns when tire pressure drops below the minimum permissible specified pressure. This can indicate one or more tires as well as the spare tire. If this is the case, the warning symbol appears together with the message Tire pressure!
Malfunctions
A malfunction can have various causes.
If the tire pressure monitoring system is not available, the tire symbol appears in the display. This can have various causes.
- If the message appears at the end of the learning process, the system cannot recognize the wheels installed on the vehicle. This can be because one or more wheels without a wheel sensor were installed.
- A wheel sensor or other component may have failed.
- The system has detected more than 5 wheels in the vehicle, for example when carrying snow tires.
- A tire was changed but the Initialize wheels function was not performed.
- If snow chains are being used, system function can be compromised due to the shielding properties of the chains
- The system is not available due to a malfunction.
- Other transmitting devices with the same frequency, for example, headphones with integrated radio or other transmitters, are emitting an electro-magnetic field which can cause a temporary interference with the system.
- Try to find the cause of the interference, and then perform the Initialize wheels one more time. If this still does not fix the problem, contact your authorized Audi dealer for assistance.