First, my 420SEL has an interior temperature sensor located overhead next to the dome light - correct? Lately a squeek has started in the vicinity of the sensor, beginning as soon as I start the engine.... is there a tiny fan associated with the temperature sensor? The squeek sounds like a tiny bearing going bad, and is driving me crazy. I have looked in various parts catalogues, including fastlane, and can't find a fan associated with the temperature sensor. I recall a discussion in forum a year or so ago regarding such a fan, and I searched with various key words...but couldn't come up with anything. What else in the overhead dome light structure could cause such a squeek? Hint - the squeek goes away when I put my hand over the temperature sensor opening......

JoeB