I have the factory service manual for this car and in the section on cooling it tells what models/engine had what fan. And it lists it right in there that that was a factory setup on some 318 ac cars.
And in the comments on the door lock things... I've tried the disable thing listed many times over the last 10 years I've had this thing, and IT DON'T WORK to disable that so called "feature". I know you used 99 as an example, my particular Durango is an 01.