Just purchased a 2008 TL. Drove for the past three days in 30 degree weather (F) and I can NOT keep any of the windows clear of fog without running the defrost function on HIGH FAN continually (tried it with RECIRC on and off, on produces better results! I have the A/C on and the defrost button selectednad heat temp HIGH. The rear passenger windows NEVER get de-fogged! What is going to happen when it really gets cold here in Michigan??? HELP!! Seems to me the A/C might not be working properly. Taking to dealer tomorrow.

 

Check for moisture (wet) on the ft pasenger floor mat. Although rare, this sounds like a heater core.

 

ltkaufman

Thanks for the heads up! I will check it out! Now that you mention it...it does smell a bit like radiator / heater core at times.

 

Problem resolved by dealership. CAUSE= They found that the foil from dash insulation was NOT REMOVED from the fresh air inlet hole at the factory. They cut out the air inlet and reassembled...now operating normally!!! Just my luck, to pick this one off of the lot!!!

 

at least it was an easy fix dor them and didn't have to tare the car apart