1994 Holiday Rambler Diesel Pusher Engine compartment blower

the back of the motorhome has a louvered vent on each side, nothing connected to them, and yes the blower runs anytime the engine is running.I have not seen anything like this on other coaches, only a side grill if you had a side mounted radiator.
Thanks again for all the replies. I would show a picture but I dont know how to just add it to a message. The pic is on my laptop, not at a url