B5Burn

Be careful of which sensor you are referring to... I think you should go by shape and not the colour to help save with confusion.

One has a roundish connector (LIGHT green sensor), and one is square (BLUE sensor). REGARDLESS of colour... replace with the correct shape.(or use a part number of course).

I had a little blowout with the parts guy at the dealership about this... the sensor I yanked from my car was a sky blue colour. I went in with part numbers and did not look at the sensor on my car before going in... I was sold a sensor that was Forest Green (very dark green)... I called the guy right back and I said I think I have the incorrect unit.... he said no, I sold you the Blue one... and I was like, "umm.. I am not colour blind, this is Dark GREEN.. I just about had to go down to have a chat regarding colour (I work in design, I frikking know the diff between blue and green!!!).. I thought he was colour blind.... anyway, after a phone chat, he said, well the new sensor has some green in it, but it's still blue... but it's dark GREEN, definitely not Blue. He said this colour replaced the former light blue unit. And they still refer to it as Blue, even though its GREEN!! The other sensor is light green, as I mentioned.. but you can't plug the wrong one in due to the plug style that fits in it.

I was following this tech article;<ul><li><a href="https://www.audiworld.com/tech/eng54.shtml">https://www.audiworld.com/tech/eng54.shtml</a</li></ul>

B5Burn

<center><img src="http://members.shaw.ca/billreburn/greennotblue.jpg"></center><p>Here you can see the difference.. the guy at the dealership thought this sensor (which is mostly covered by the plug it fits into) was Blue... the plug is def Blue.. but my previous sensor was the same Blue as the plug... it's not that Blue anymore.

Square or Round

Neo1130

Also, it is not that sensor that controls the fan... That one is on the lower rad hose...

inigo

The blue 4pin (square) dual temp sensor only comes in one type.

The green 4pin (D shape connector) dual temp sensor comes in a few different varieties (temp range).