There is a black plastic blob/disk/pod behind my rear view mirror on my 2008 F150 SCrew XLT. This truck does not have auto-dimming mirrors. I'm guessing it is a compass reading nodule, or it is an fm transmitter for the sirius antenna on the roof.

Do I win anything? And for WHICH answer?

 

compass

 

I think its for temperature, I have the black blob in my truck and I dont have compass, so I dont think its that
Im gonna say its for temperature

---Ok correcting my post, had my truck over a year now, have 15K miles and never new I had a compass in my truck untill I looked this morning, worse yet its 1/2" to the left of the temperature reading. So ill agree its the compass

 

Its both. Temperature and compass.

 

no its the compass. the outside temp sensor is behind the grill in the center of the radiator. the black "blob" even has a button on it and when pressed the compass will say CAL and will calibrate if you drive around in a circle.

 

compass only on the rear mirror


the temp is out on the radiator support behind the grille. a little black sensor thingy that sits about 1/2 down the support beneath the hood latch

 

Thanks everyone!

I'm a newbie to this truck, so am just trying to figure out what is what.

I need to buy a helm manual for it!

 

Oh and speaking of black blob behind the mirror, if anybody cares because of that black blob not many tint companies will remove it to put on the tint strip on the windshield, when I had mine done they put a vinyl strip on the outside(looks better anyways) because they wouldnt have anything to do with the mirror and the black blob, to expensive to fix if they broke it