Transmission Cooler runs (and runs and runs)

[Russell Marlowe]

Newbie M380 owner. What I believe is my transmission cooler (driver's side, rear bay) is running ALL the time. The coach hasn't been driven in 2 weeks.

If I shut down power to the coach, it will stop, but that's the only way I have found. At first I thought it was related to the a/c but apparently that is not it.

I'm wildly guessing that some sender unit somewhere thinks that the transmission needs to be cooled down, but I don't have a clue where to even begin to look.

Thanks for any help, advice, or ideas.