After purchasing my new 2012 Prius liftback, I discovered that the Prius air inlet mode automatically and randomly switches between recirculate and outside air mode (in cold weather). This means that without warning, the Prius will switch to outside air mode, forcing me to inhale exhaust from the vehicle in front of me, which gives me an asthma attack.
Toyota claims this design feature cannot be fixed. However, on the 2010 Prius, which is the same generation as my 2012 Prius, it is possible to use Toyota’s diagnostic software Techstream Lite to set the air inlet mode to manual, overriding the automatic switching to outside air mode. In addition, for the 2012 Prius, this air inlet mode customization is available on Priuses sold in Korea and Mexico:
I have received no assistance from Toyota on this matter, and now that the cold weather has arrived, driving my Prius has become unbearable due to the automatic switching to outside air mode (I’ve already suffered an asthma attack as a result of exhaust entering the cabin). I guess I have 2 options: sell my Prius or figure out how to fix this myself. Can anyone point me in the right direction about how to edit the Prius software? It would be helpful to see how the manual recirc override in the 2012 Prius in Mexico and Korea is programmed and/or how the 2010 US Prius override is programmed. I would greatly appreciate any assistance!
Also, is this the kind of question Click and Clack might answer? If so, should I submit it as a question for their column or “ask a puzzler” or…?