AUDI Outside Air Temperature Readings

AUDI Outside Air Temperature Readings

Incorrect readings can be avoided.

To achieve a smoothening effect of the displayed outside ambient temperature, the value shown does not instantaneously follow the temperature sensor measurement. The display won’t change any faster than 4° F per minute. This concept applies to both falling and rising temperatures. A programming strategy is also implemented to avoid incorrect readings on a parked vehicle, due to the temperature sensor being affected by outside influences such as radiant heat from the engine bay, elevated road surface temperatures, etc. Incorrect readings are avoided through the following logic: 

  • After switching the ignition on, temperature changes are shown only after 30 seconds for a stationary vehicle (vehicle speed = zero and the engine switched off). 
  • Only when the vehicle drives faster than 12 mph, rising temperature values are displayed during the first three miles. 
  • If the measured ambient temperature is above the displayed value but falling, the display is not changed. 
  • When the coolant temperature reaches 104° F and the speed drops to under 12 mph, only falling ambient temperature values are shown. For example, in stop-and-go traffic when the vehicle is often below 12 mph, it can take some time before the displayed temperature is correct. 

If the conditions above are noted during these typical driving scenarios, the sensor is not at fault and does not need to be replaced.

You May Also Like

Tech Tip: Checking Transmission Fluid Levels When Cold or Hot

Checking the fluid level before the transmission has reached the specified temperature might cause a false reading

Any transmission fluid will increase in volume as it is heated. Many CVT fluid manufacturers have a recommended temperature range to check and set the level. This temperature needs to be checked using the sensor mounted to the valve body. Guessing the temperature or using an infrared thermometer on the pan is not an option.

Why Do Turbos Fail?

In the 1980s, it was not uncommon for a turbocharger on some European vehicles to last only 30,000 to 40,000 miles. The failures were almost always in the center section and caused by the lack of oil to cool and lubricate the bearings and shaft.  Related Articles – Servicing Mercedes-Benz AMG Brakes – Air Ride

Servicing Mercedes-Benz AMG Brakes

Take a look at some of the things you need to know in order to service the brakes on a Mercedes-Benz AMG vehicle.

Air Ride Diagnostics: Reservoirs and Compressors

The secret to diagnosing air ride problems is knowing what criteria the system uses to regulate the compressor/reservoir and having the right tool.

BMW 4-Series Service

The 4-series does not stray far from the typical BMW engineering and operation.

Other Posts

Audi A New Seal on The Block

The PTFE seal provides a wider operating temperature and a low coefficient of friction.

Audi MLB Alignment

The alignment of these vehicles can be straightforward mechanically.

VW HVAC Service

Volkswagen HVAC systems have come a long way.

BMW DSC Module 

If any of the situations apply, follow the correction procedure.