is this the 1st time yours does this?
Ive posted a step/flow of how the computer updates the temp... that should be similar to the lambdas... it basically does not update temps right away under certain conditions.
But if youve noticed it change right away in similar conditions- then try the reset and if it still acts up- swap it out.
The outside air temperature is displayed on the Driver Information Center (Fig.
, radio or rear view mirror in a number of GM vehicles. There may be some confusion about the operation of the display and how quickly it updates ambient temperature. Depending on several factors, the temperature may not be updated immediately and owners may feel that the display is inaccurate at times.
As an example, here's a look at the operation of the outside air temperature display on several GM small cars from recent model years (2004-2007 Malibu/Maxx; 2005-2010 Cobalt and G6; 2005-2006 Pursuit [Canada]; 2006-2009 Solstice; 2006-2011 HHR; 2007-2010 AURA, SKY and G5; 2008 Malibu Classic; 2008-2010 Malibu).
The ambient air temperature sensor is a variable resistor interfaced to the Body Control Module (BCM). The BCM provides the logic for reading the ambient air temperature sensor, filtering the data and transmitting the information via the serial data circuit to the outside temperature display. The outside air temperature algorithm uses three pieces of information: outside air temperature data, vehicle speed, and the time the engine was turned off.
When the engine is first started, the algorithm looks at how long the engine was off and if the outside temperature is lower than the last reading taken during the previous ignition cycle. From this information, it's determined if a new outside temperature reading should be taken.
If the engine was off long enough or the current outside air temperature is cooler than the stored value, a new outside temperature reading is taken and displayed. If the engine was not off long enough or the current outside air temperature is higher than the stored value from the previous ignition cycle, the last stored value of outside air temperature taken will be displayed.
The outside air temperature will continue to be updated every second as long as the outside air temperature is the same or cooler than the previous reading. Once the new outside air temperature reading exceeds the previous temperature and the vehicle is traveling less than 18 mph (29 km/h), the displayed outside air temperature will remain at its last value. Once the vehicle speed exceeds 18 mph, the displayed outside air temperature will be updated. If the speed drops below 18 mph, the outside air temperature will freeze at its last value.
When using a scan tool during diagnosis, it is possible that the temperature reading on the Tech 2 will differ from the temperature displayed on the DIC/radio without there being a problem with the vehicle. The DIC/Radio only displays the reading being sent from the BCM.
TIP: Do not replace the ambient air temperature sensor or the BCM for an inaccurate outside air temperature display condition.