Hey there. My car used to do the same thing after driving it. It seems normal for larger cars with V6 engines to cool the engine after driving to minimize damage to the aluminum heads, especially Hondas and other derivatives. It can happen if you live in a hilly area or drive it extra hard right before parking it. Under light driving conditions, it may not turn on, but if you come outside to a dead battery, those fans were running for too long and the problem needs to be investigated. If anyone has any extra input, please chime in.