Ditto. It is very well worth pulling yoru dash apart to clean that bugger. There is a small fany that draws air into the sensor. Naturally this also draws in Cocker Spaniel hair, balding owner hair , trail dust ans worst of all, moisture. This makes for a nice collection of goo and "fluff" that can eventually render the fan stuck and the sensor useless. Once I cleaned mine out the first time I found a quick spray with compressed air each oil change keeps it nice and clean.