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Oily-liquid dripping from front center part of large battery pack under Tesla Model S

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Hi,

I have a 2015 Tesla Model S and recently found this liquid to be dripping (quite significantly) from the front and center part of the battery pack. It was after a long drive so very possible something flew up and hit something on the freeway.

I have attached images of the oily like substance below.

IMG_4294.jpeg
IMG_4295.jpeg
 
It sure looks oily for AC condensation. It also looks too oily for coolant, unless a drive unit or something with lubricant is leaking into the coolant. Need to find the source.
The colors in the oily layer seem consistent with an oil slick on water, that is a molecule thick layer of oil on water where the thickness of the oil layer interacts with visible light to generate those colors. If the underlying liquid was oil, I would expect the oil to spread out immediately on the surface of that asphalt. It looks to me as if it slowly wetting the asphalt at the edge of the stream so I continue to think the main bulk of the fluid is water. If it was a stream of oil I would not expect to see those colors.

If it is water then the most likely source after a long trip in the summer would be air conditioning condensate. He lists the source as from 2 areas of the battery pack. A puncture road object caused puncture on the battery pack should come from a single point on the bottom of the battery pack. If there’s wanter coming from a plugged or displaced A/C drain hose he might see an ambiguous source. The Northwest has had warmer than normal temperatures. Anyway if he has identified separate discrete puddle of water from the A/C he might be able to eliminate the A/C drainage as a source.

I believe the fresh asphalt may be a source of that thin layer of oil. There’s some subtle difference in the color of the asphalt so there may have been oil on the surface of the asphalt before this liquid was deposited.

All this is a guess. Right now I think water is the most likely explanation. He didn’t mention washing the car recently or a recent exposure to rain but Seattle Wa does see an enormous amount of rain. The windshield washer could be a source but usually washer fluid has various solvents and surface active agents to make it a better cleaner. Still if the washer has been repeatedly filled with plain water, it could be a source.

The car is 7 years old so a plugged or displaced A/C drain hose is my best guess.

When you definitively identify the cause, please would you let us know. If I’m wrong I’ll learn something so that’s always worthwhile.
 
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