According to the factory service manual when the AC is turned or the water temp. reaches 110 degrees C the electric fan is supposed to come on to help cool the AC condensor.However, this does not happen and the MIL lights up on the Information Center. The fan relay is ok and the fan works fine when I apply 12 V to the fan side of the connector at the bottom of the radiator. The code indicated is P 1491. After the MIL appears and you drive for a while it disappears after stopping and restarting the engine. Does anyone have any suggestions besides taking the Durango to a shop with a DRB to scan for the problem?...........